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(NEW YORK) — The leading 2024 Republican presidential candidates are set to face off in a series of debates — the first of which is Wednesday night in Milwaukee, airing on Fox News starting at 9 p.m. EDT.

More than half a dozen White House hopefuls have met the polling and donor requirements for a spot on the debate stage. The front-runner, however, has declined to participate outright.

Here’s what to know about the first Republican presidential primary debate and the debates coming later in the election season.

How to watch the debate
The two-hour debate will air on Fox News and anchors Bret Baier and Martha MacCallum will moderate it.

ABC News and FiveThirtyEight will have live updates online of the latest action on the debate stage as well as analysis on the biggest takeaways from the night.

Who will be participating in the presidential debate?
Eight candidates are confirmed to have met the Republican National Committee qualifications to attend.

They are: Florida Gov. Ron DeSantis, former New Jersey Gov. Chris Christie, former Vice President Mike Pence, tech entrepreneur Vivek Ramaswamy, former South Carolina Gov. Nikki Haley, South Carolina Sen. Tim Scott, North Dakota Gov. Doug Burgum and former Arkansas Gov. Asa Hutchinson.

The RNC on Tuesday announced the lineup for where candidates will stand on the stage during the debate. DeSantis and Ramaswamy will stand center stage; Pence will stand to DeSantis’ right and Haley will be to Ramaswamy’s left.

The RNC shared earlier this summer that it would place candidates according to their polling numbers — with the highest polling candidate in the center.

Here’s a look at where each candidate will stand during the debate:

Former President Donald Trump would also have qualified — except that he isn’t going. He wrote in a post on his social media site on Sunday that he will skip the debate, saying that the public already knows who he is. He has also cited his enormous lead in early polls.

The GOP front-runner will instead release a pre-recorded interview with former Fox News host Tucker Carlson on Wednesday, a source familiar with the matter confirmed to ABC News over the weekend.

Miami Mayor Francis Suarez, former Texas Rep. Will Hurd, conservative radio host Larry Elder and businessman Perry Johnson did not meet the requirements to qualify for the debate.

What do candidates have to do to qualify for the debate stage?
The RNC set polling and donor requirements that candidates needed to fulfill to get on the first debate stage.

To qualify in Milwaukee, candidates needed to earn at least 1% in three high-quality national polls or a mix of national and early-state polls between July 1 and Monday. Also, they must have a minimum of 40,000 donors, with at least 200 donors in 20 or more states.

Additionally, candidates must also sign the pledge to support the eventual party nominee and not participate in non-RNC sanctioned debates.

The format and topics of the first debate
Candidates are expected to tackle many different topics.

While Trump isn’t expected to attend, he will likely be part of the discussion. The former president is facing four criminal indictments, and how other candidates react to his charges will “be interesting,” moderator Baier told Deadline.

“In the GOP primary, we have seen these indictments increase his polling numbers, increase his fundraising. … How others react to it and how differently they approach it will be a part of this primary and this debate,” Baier said.

Trump has denied any wrongdoing.

Abortion and the U.S. role in Ukraine amid Russia’s invasion are also topics the moderators plan to ask candidates about during the debate, MacCullum told TVNewser.

The candidates will not give opening statements and will have one minute to answer questions. They will have 30 seconds to respond to follow-ups and 45 seconds for closing statements, according to details Fox News shared with candidates ahead of the debate.

“Best efforts will be made to ensure a fair and robust discussion, giving every candidate the opportunity to answer questions and react to others,” the candidate-provided debate details state.

Mics will be attached to all candidate podiums and will be turned on at all times.

Why is the first debate in Milwaukee?
Republicans chose Milwaukee for the location of the first debate and for the Republican National Convention in July 2024, a likely reflection of Wisconsin’s electoral importance as a key swing state.

Four of the past six presidential elections have been decided by less than a percentage point in Wisconsin. In 2020, President Joe Biden won by only about 21,000 votes — a .56% margin; in 2016, Trump won with .77%.

When are the other 2024 presidential debates scheduled?
The second debate will take place on Wednesday, Sept. 27, at the Ronald Reagan Presidential Library in Simi Valley, California.

Haley has reportedly indicated the third debate will be in Alabama in October, though RNC officials haven’t confirmed that.

ABC News’ Lalee Ibssa, Soo Rin Kim and Isabella Murray contributed to this report.

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