MIAMI (AP) — After circling each other for months, Democratic presidential candidates will converge on the debate stage in Miami on Wednesday as the campaign enters a new — and likely more contentious — phase.

Given the massive field , the debate will be split over two nights with 10 candidates appearing each evening. It’s the highest-profile opportunity yet for many White House hopefuls to offer their vision for the country and — if for just two hours — chip into a political news cycle often dominated by President Donald Trump.

Elizabeth Warren will take center stage at the debate’s opening night. The Massachusetts senator’s constant stream of policy proposals has helped her campaign gain ground, and she’s the sole top-tier candidate who will appear at the Wednesday debate. Widely viewed as a talented debater, Warren is well positioned to showcase her strengths, strategists say.

Beyond Warren, the candidates who will debate on Wednesday are Sens. Cory Booker of New Jersey and Amy Klobuchar of Minnesota, Reps. Tulsi Gabbard of Hawaii and Tim Ryan of Ohio and former Reps. Beto O’Rourke of Texas and John Delaney of Maryland, along with Washington Gov. Jay Inslee, New York City Mayor Bill de Blasio and ex-Obama housing secretary Julián Castro.

One split that could emerge Wednesday centers on “Medicare for All,”the single-payer health plan introduced by Vermont Sen. Bernie Sanders, a fellow Democratic presidential candidate, and supported by Warren and others. But some candidates are not fully on board, preferring more incremental reforms. Delaney has been especially vocal in his criticism.

With so many White House hopefuls on stage, it could be difficult to dive too deep on any given issue. NBC News, which is hosting the debate, said candidates will have 60 seconds to answer questions and 30 seconds for follow-ups. They will be allowed closing statements but no openers.

All the candidates are competing ahead of a major fundraising deadline that will have lasting implications. The end of the second fundraising quarter on Sunday gives candidates a chance to make a splash with strong numbers ahead of the mid-July deadline to report that information to the Federal Election Commission.

A strong debate performance could fuel more donations, which is critical to the candidates’ ability to participate in future debates. The Democratic National Committee is enforcing more stringent requirements for participating in the presidential primary debates this fall, so candidates who are struggling to gain a foothold may not have another similar opportunity on a nationally televised stage unless they are able to significantly boost their standing in the polls and fundraising numbers.

The debate will unfold as many Democratic voters are just beginning to tune in.

Only 35% of registered Democrats say they’re paying close attention to the campaign, according to a new poll from The Associated Press-NORC Center for Public Affairs Research. Two-thirds say they’re paying some or no attention.

“People may have heard (the candidates’) names, but they couldn’t pick them out and don’t know much about them,” said Jesse Ferguson, a veteran Democratic strategist. “None of them are going to seal the deal in the first debate, but they need to get people interested enough to want to learn more.

The debate’s second night on Thursday features more of the leading Democrats in the race. Former Vice President Joe Biden will stand at center stage with Sanders at his left and Mayor Pete Buttigieg of South Bend, Indiana, at his right. Biden has come under fire from fellow Democrats after recently recalling that the Senate was once a more civil place, pointing to his work with two segregationist former senators.

The remarks elicited condemnation from his rivals, notably Booker and Sen. Kamala Harris of California, who raised questions about Biden’s understanding of the history of segregation. Booker, who was among Biden’s sharpest critics, called on him to apologize.

Were the two candidates to share a stage, the episode could have been a defining moment of the debate, with the two men discussing the issue in real time. But Booker will take the stage on Wednesday, with Biden and Harris among the candidates to follow on Thursday.

If Booker were to bring up the episode, or respond to a moderator’s question about it, Payne said, “it’s almost like he’s attacking him in absentia.”

A memo released by the Booker campaign ahead of the debate said their goal was “straightforward: Cory will look to introduce himself to voters just tuning in to the race.”

Several of the candidates went to Florida early to raise money or court voters in the critical battleground state. Buttigieg held two Florida fundraisers on Monday night and stayed in Florida for debate prep. Warren, meanwhile, was in the state on Tuesday to campaign for her new proposal to boost election security .

Not to be outdone, Vice President Mike Pence was also in Miami on Tuesday to launch “Latinos for Trump” as part of an effort to engage Latino voters for 2020.