(CNN) -- Tonight, 10 challengers for the Democratic 2020 presidential nomination will face off in the first debate of the season. After months of campaign coverage, the two-hour event will finally give voters a chance to watch Democratic candidates exchange views on a variety of issues, from health care and immigration to taxes and climate change. While they will likely spend a fair amount of time attacking the policies of President Donald Trump, the debate will also be an opportunity for candidates to draw contrasts with each other and tout their signature issues in front of a national audience.
For Jay Inslee, tonight will be a chance to lay out details of his climate agenda, while Beto O'Rourke and Julian Castro will likely spend time discussing immigration, which has dominated much of their talking points on the campaign trail. Cory Booker has made criminal justice reform a signature issue of his campaign, while former Maryland congressman John Delaney may try to differentiate his plan to ensure all Americans have healthcare from Elizabeth Warren's Medicare for All proposal.
Among those on the stage this evening in Miami, Warren leads the pack according to CNN's latest polling. Overall, she is currently neck and neck with Vermont Sen. Bernie Sanders for second place behind former vice president Joe Biden (both of whom will participate in tomorrow's debate).
Other notables include Booker and O'Rourke, who according to a recent Monmouth University poll, are each polling at 2%. The rest of the pack likely see this as their moment to break out from the 1% (or, in some cases, 0%) rut.
Here's a look at some of the policies and issues these candidates have promoted during their campaigns and topics they're likely to touch on this evening.
Candidates are listed in order according to their current poll numbers.
1. Elizabeth Warren
The notoriously detail-oriented Massachusetts Senator has rolled out a broad set of policy initiatives that rival any of her opponents in terms of scope. On the trail, Warren has talked taxes, health care and climate change, with a focus on specifics. Warren's wonkish approach has contributed to her steady rise in the polls in recent weeks, and distinguished her as the candidate with "a plan for that."
Taxes
Warren has repeatedly pushed for a wealth tax on people whose net worth exceeds $50 million. Over 10 years, Warren claims, the tax would generate some $2.75 trillion for the government.
She says the tax would pay for a number of her other initiatives, including universal pre-school, universal college and more.
"You've been paying a wealth tax forever. It's a property tax that you've been paying on your biggest asset," Warren said. "All I'm proposing is for the biggest fortunes in this country to include the stock portfolio, the diamonds, and the yachts."
Health care
Warren has previously supported Medicare for All or a Medicaid buy-in as a means for achieving universal coverage. But at an Aurora, Colorado, town hall in April, and in more recent campaign stops, Warren has argued that Medicare should be the way to move forward with universal coverage.
"Lots of different pathways, but we know where we're headed. Where we're headed is 100% coverage for all of all families at the lowest possible cost," Warren said, "and Medicare is the way to do this."
Big tech
Warren has advocated breaking up big tech companies like Google, Amazon and Facebook in an effort, as she sees it, to create more competition in the digital marketplace.
"America has a long tradition of breaking up companies when they have become too big and dominant," Warren wrote in a blog post announcing her proposal, "even if they are generally providing good service at a reasonable price."
2. Cory Booker
As part of his 2020 campaign, the former Newark mayor and current New Jersey Sen. Cory Booker has focused on criminal justice reform, his "baby bonds" proposal and extending the Earned Income Tax Credit to help close wealth gaps. Booker has recently made headlines by attacking Biden for his comments about working with former segregationist Senators.
Criminal Justice Reform
Following the bipartisan passage of the First Step Act, a criminal justice reform bill signed into law by Trump, Cory Booker co-authored the Next Step Act. The bill calls for larger reforms focused on prison conditions, sentencing guidelines including a reduction in mandatory minimums for nonviolent drug offenses.
"This bill is a meaningful step in the right direction that will help correct the ills of the failed War on Drugs," Booker wrote in a press release. "It will have a profound effect on thousands of families suffering under the burden of our broken system."
Booker has also called for an end to private prisons and recently said that if elected he would start a clemency review for some 20,000 federal prisoners convicted on non-violent drug charges on day one of his presidency.
Baby bonds
Booker's baby-bond system would set up a savings account for every US citizen once they're born. Depending on family income status, each kid would receive a yearly deposit from the government in their savings account. Once they turn 18, the funds could be accessed for approved uses like higher education and homeownership.
"At birth, every American child would be given an 'American Opportunity Account' seeded with $1,000," a press release from Booker says. "Each year, children would receive up to an additional $2,000 deposit into their American Opportunity Account, depending on family income."
Tax credits
Booker has proposed greatly expanding the Earned Income Tax Credit to more middle- and working-class families. At a local Democratic Party event in Nevada in April, Booker called his plan, dubbed the Rise Credit, a "simple, common-sense" solution.
"A couple making up to $90K a year, individual to $54K a year, you'll get a direct tax credit," Booker said. "The working people get an extra $4,000 tax credit; Couples, up to $8,000."
3. Beto O'Rourke
The former Congressman is going for the presidency fresh off his nearly-successful bid to unseat Sen. Ted Cruz in Texas last year. Here's how he sets himself apart from his competitors.
Immigration
In addition to giving undocumented immigrants access to the nation's health care system, O'Rourke has called for an immediate path to citizenship for the country's 700,000 DACA recipients, also known as Dreamers.
"The 10 or 20 year pathway makes absolutely no sense if we consider our own self-interest, in terms of what those Dreamers are already doing and what more they could do if US citizens," O'Rourke said at a reception for the Asian and Latino Coalition in May.
O'Rourke said in April he would increase foreign aid funding to Guatemala, Honduras and El Salvador, which the Trump Administration has cut.
He has proposed dramatically reducing the detention of immigrants seeking asylum to include only those who had committed crimes and were seen as dangerous, and would wind down the use of private prisons to house those immigrants. And O'Rourke has stridently opposed Trump's push for a border wall, saying the wall currently in place in El Paso has not worked and that he would prefer to tear it down.
Health Care
O'Rourke says his aim is universal health care, but has stopped short of pushing for a single-payer system. He backs "Medicare for America," a plan by Reps. Rosa DeLauro of Connecticut and Jan Schakowsky of Illinois. It would maintain a role for private insurance, but move those receiving government-funded health care -- as well as those who prefer it to their private insurance -- onto Medicare.
He has also called for the prosecution of executives at Oxycontin manufacturer Purdue Pharma over the company's role in the opioid crisis.
Taxes
In Iowa, O'Rourke said he would tax capital similarly to how income is taxed now and reinvest the money to spur economic growth.
O'Rourke has also proposed a "war tax" to help pay for care of the veterans of future wars. It would only be implemented when new wars are authorized and would range from $25 for households making less than $30,000 per year to $1,000 for those making $200,000 a year or more.
4. Julian Castro
A former secretary of Housing and Urban Development, Julian Castro has cast his candidacy as a rebuke to Trump's tough talk on migrants crossing the southern border. The former San Antonio mayor has long been viewed as a rising star in the Democratic Party and hopes to capitalize with a platform heavy on immigration policy.
Immigration
Castro told The Atlantic last week that he would seek to make crossing the border illegally a civil offense as opposed to a crime.
"I would actually treat it as a civil violation and create an independent immigration judiciary, and add more judges and support staff to be able to get people seeking asylum, or who are otherwise in that immigration judicial process, an answer, so people aren't waiting in limbo for years," Castro said.
Castro also called for a path to citizenship for the 11 million people living undocumented in the US, including Dreamers and their parents, in a Medium post outlining his immigration plan. That includes funding what he calls a "21st century Marshall Plan for Central America," that would focus on stabilizing countries that are the biggest sources of migration to the US.
"It's time that we recognize that protecting our borders and treating immigrants with compassion are not mutually exclusive," Castro wrote in April.
Health care
Castro also told The Atlantic he supports "major reform" to the health care system, allowing anyone who wants Medicare to get it.
"I support everybody who wants Medicare to get Medicare, and if somebody has private insurance that they want to hold on to, I believe that's fine as well," Castro said.
Castro told the Des Moines Register in February he supports Medicare for All but wants to keep an option for supplemental private insurance.
Gun control
At a CNN Town Hall in April, Castro mentioned three methods of gun control he supports: limiting the capacity of weapons, universal background checks and a gun buyback program.
"We also need to limit the capacity of magazines, and we need to make sure that we do everything that we can so that people who get their hands on guns do so in a safe way," Castro said. "So, you know, I support making sure that we make those background checks universal. I support things like gun buybacks."
5. Tulsi Gabbard
The first Samoan American and first Hindu American to serve in Congress, Gabbard has focused her 2020 campaign on green energy and foreign policy.
Environment
Gabbard considers herself a lifelong environmentalist. By 2035, the US will be completely transitioned to clean energy, according to her OFF Fossil Fuels Act.
"I'll tackle climate change by ushering in a green century, ending taxpayer subsidies for these fossil fuel giants and multinational agribusiness corporations, harnessing the technology and innovation that we have to create jobs in renewable energy," she said.
She takes it a step further than other candidates by also focusing on land and water conservation and a ban of harmful pesticides.
Foreign Policy
As an Iraq war veteran, Gabbard brings a unique point of view to foreign relations.
"We've got to take on the threats to national security, threats like al Qaeda and ISIS and defeat those threats," she said in an interview with the New York Times. "I will end the wasteful regime change wars that have taken such a toll on our troops and on the American people, with the trillions of dollars that we've spent on these wars."
Gabbard has called for returning to the Iran Nuclear Deal, as well as expanding Congress' influence over matters of foreign military intervention. On trade, she remains critical of NAFTA and TPP.
Healthcare
Gabbard is a big supporter of Medicare for All.
"We must stand up against big pharma and insurance companies who extort those who are sick, who put their profits above the health and well-being of our people," she said when she announced her candidacy. "We have to fight to make sure that every single American gets the quality healthcare that they need through Medicare for all."
Along with universal healthcare, she wants more government oversight of drugs and their prices.
6. Amy Klobuchar
The first elected female senator from Minnesota, Klobuchar has already outlined what she will do in her first 100 days in the White House. Climate change is first on the list.
Climate Change
A co-sponsor of the Green New Deal, Klobuchar has been a vocal candidate on restoring efforts to fight climate change.
"It's happening right now, and that's why as your president on day one I would get us back into the international climate change agreement," she said at the CNN Townhall in April. "On day two and day three I would bring back the clean power rules that the Obama administration worked out that will make a big dent in this. I will bring back the gas mileage standards that they just left and said, 'Oh, sorry, I know you car companies were ready to do it, but guess what, you don't have to.'"
Klobuchar said she would build on the Green New Deal to toughen building codes, support clean transportation and invest in sustainable infrastructure.
Healthcare
Klobuchar wants to give people a public option for healthcare, while letting people keep private plans, instead of overhauling the system.
"I believe that we need to provide universal coverage to every American. We have gotten closer and closer to that, but certainly we are not there. There are many ways you could get there. One of them is expanding Medicare," she said in a CNN interview in January.
Education
Teachers need pay raises and students need help paying for college, Klobuchar says time and again.
"The first thing is we need to make it easier to afford college, and you need to do that by making it easier to refinance these loans, by extending Pell grants so it includes more students. Those are simply grants, right? So if you extend those Pell grants, that's going to make it even easier because right now it's for a limited number of students," she said at a CNN Townhall in February.
Klobuchar is focused on filling vacancies at the Department of Education for oversight of civil rights violations and federal aid disbursement and funding higher education for foster children.
7. Jay Inslee
Washington governor Jay Inslee has made fighting climate change the centerpiece of his campaign. The former congressman said it should be the nation's "first, foremost and paramount duty," and his platform reflects that notion.
Climate change
Inslee said he is running on a four-pronged climate change platform when he announced his campaign in March. It involves a $9 trillion investment toward building a completely carbon-free and renewable-based economy by 2030, creating new jobs with clean energy, involving everyone in the "new" economy, and ending subsidies to fossil fuel.
"Now, these are ambitious goals," Inslee said. "And some may doubt our ability to build this new future, or say that our workers aren't up to the challenge. Well they are wrong. Don't believe them."
Inslee has dubbed his proposal as the Clean Energy for America Plan. It will require that all new light-duty passenger vehicles, medium-duty trucks and buses to emit zero emissions by 2030.
Health Care
Inslee told CNN's New Day in February he doesn't support Medicare for All, but he supports other methods like a public option or an opt-in for those who want Medicare. He did not, however, specify which he prefers.
"I don't think it's necessary. And right now, we need to embrace the things that we can have to move towards universal health care."
Minimum wage
At a strike of McDonald's workers in Chicago, Inslee said he supports raising the minimum wage to $15 an hour.
"When people tell you that if you have $15 minimum wage it's going to wreck your economy, you tell them to come out and see me in Seattle," Inslee said.
Seattle was one of the earliest jurisdictions to raise the minimum wage for large employers to $15 through gradual yearly increases. The city's minimum wage for companies with more than 500 employees globally now stands at $16. As governor, Inslee has overseen an annual increase in his state's wage to $13.50 in 2020, which voters approved in a 2016 ballot initiative.
8. Tim Ryan
Ohio Rep. Tim Ryan has been a US congressman for almost two decades and is now running on a promise to fix the economy for blue-collar workers.
Economy
Ryan is focused on rebuilding the economy through increased infrastructure spending and creating more clean-energy jobs in areas where manufacturing work has declined.
Ryan has been a leader on punishing companies that take tax cuts and then leave the country, something that has been directly experienced by his Ohio congressional district.
"We've got to get the job numbers, the wages up $30 an hour, $40 an hour, $50 an hour, so people can work hard, and if they hurt their back, they're going to want to get back to work because they have a little fishing boat, they can take their kids hunting, they can go on vacation," he said at a CNN Town Hall earlier this month.
He emphasizes wage growth, public-private business partnerships on a local level and an incentive for other countries to invest in the US.
Healthcare
Ryan has supported Medicare for All, but he stresses the need to keep private healthcare as an option.
"And there's story after story after story of people then getting denied treatment, going home and within weeks taking their own lives," Ryan said in an MSNBC interview. "It's our veterans, it's our farmers, it's our teenagers. This is out of control. This is a national crisis. We've got to pay attention to it."
He wants to bring oversight to insurance companies and make public healthcare an option.
Education
Ryan believes in tuition-free, debt-free college for all. His congressional office said that Ryan's plan would be paid for by "a tax on Wall Street speculation."
"Education is critical to personal flourishing as well as keeping the American workforce competitive in an increasingly globalized economy," he said in a statement. "College should not only be for the privileged few."
If elected, Ryan says he would make four-year public institutions free to attend and would allocate more funds to federal student aid.
9. Bill de Blasio
A late starter in the 2020 race, New York Mayor Bill de Blasio has made headlines by constantly attacking Trump (or, 'Con Don' as de Blasio dubbed him.) De Blasio has shown a willingness to fault his opponents, something he did stridently when he knocked Biden's view on abortion rights.
While he talks about his tenure as the mayor of the nation's largest city, he rarely talks about his deep unpopularity there or the challenges he has endured in office.
Here are some of the main policies he's touted during his tenure as Mayor.
Universal Pre-K
De Blasio has long held up the universal public pre-Kindergarten program in New York City -- which launched in 2014 -- as his most significant legislative success as mayor. The program has expanded from serving an initial 19,000 children to now enrolling about 70,000, according to the New York Times.
While many candidates have promised universal pre-K as part of their 2020 campaigns, de Blasio will likely use this program as proof that he can deliver on this promise.
Abortion
De Blasio supported New York's expansion of abortion access in the state and has attacked the recent legislation passed in Alabama as well as Biden's previous support of the Hyde amendment.
In tweeting about the recent anti-abortion legislation that passed in Alabama, de Blasio wrote "this is what the radical right is using to strike down Roe v. Wade. We're in the fight of our lives and can't back down."
De Blasio has announced a budget agreement with the City Council that abortion activists say would make New York City the first city to provide public funds for abortions.
10. John Delaney
Former congressman of Maryland and father-of-four John Delaney was the first in line to take on Trump in 2020 but has struggled to gain traction. He is one of the few candidates who frequently calls out his Democratic rivals for policies he believes are too liberal and too expensive.
Health care
Delaney thinks healthcare is a right, but says he has a better option than the "intellectually dishonest" Medicare for All.
"Unlike the new Medicare For All bill, my plan is fully paid for. Health care should be a right for every American, but it needs to be based on a smart approach. As a former health care entrepreneur, I know how the system works. That's why I have a common sense plan that covers every single citizen but still maintains a private marketplace," he said in a statement in April.
His "BetterCare" would create a new universal public healthcare program with an option to opt out and buy private healthcare.
Climate Change
Delaney sees the threat of climate change creatively: as an opportunity to create jobs and unify communities. He wants America to be net-zero by 2050.
"Time is of the essence on climate - we can't afford talk, we need action. That's why I support my bipartisan carbon tax-dividend proposal. There is a path for it to become law and it should be our focus," he Tweeted in February.
His tax on carbon will dissuade people from traditional fuel sources and fund technology to vacuum carbon out of the air. He also wants to create something called the "climate corps," a group of young people who travel the country aiding people to make sustainable infrastructure.
Gun Control
Delaney has run on a commitment to ban assault style weapons and closing the so-called boyfriend loophole, which would further restrict an abusive domestic partner or stalker from owning a firearm.
"A majority of the American people want us to address gun violence and to take concrete actions to make our communities safer," Delaney said. "It is time to get this done, because no one should feel unsafe at school, at work, at the movies or anywhere else. We can't let tragedy after tragedy happen and do nothing."