Our guide to the first Republican Debate: Everything you need to know about the event tonight in prime time and the GOP's eight candidates (with Trump skipping the big showdown)

• Showdown begins at 9 pm ET and can be seen on Fox News
• Ron DeSantis and Vivek Ramaswamy are in center stage and expected to be the top targets
• The eight GOP candidates appearing on stage will fight for a breakout moment
• READ: Follow DailyMail.com's coverage of the Republican debate in our live blog

Eight Republican contenders will take the stage in Milwaukee on Wednesday night in a high-stakes debate that will see them fight for a breakout moment that can set fire to their presidential campaign.

But the candidate who gets the most attention may end up being the one not in the room: Donald Trump. 

Trump refused to attend the debate but is expected to dominate it - just as he leads his rivals in the polls by double digits. In fact he's so far ahead that even if one of the candidates has a viral moment it may not be enough to gain ground on the former president, who will be back in the news on Thursday when he arrives in Atlanta for his arraignment in Georgia's election interference case. 

'I don't think a lot of people Thursday morning are going to be talking about what happens here at this little league game,' Trump ally Kari Lake told DailyMail.com in an interview in front of the Fiserv Forum in Milwaukee, where the debate will take place.

The race for the 2024 Republican presidential nomination has been going on for months but Wednesday will mark the first night most Americans will be paying attention. 

And that means millions of viewers will be tuning in to Fox News at 9 pm ET to see the candidates make their case. 

All the contenders: Florida Gov. Ron DeSantis, biotech entrepreneur Vivek Ramaswamy, former Vice President Mike Pence, Ambassador Nikki Haley, former New Jersey Gov. Chris Christie, Senator Tim Scott, former Arkansas Gov. Asa Hutchinson and North Dakota Gov. Doug Bergum are aware they need to take advantage of the moment to make their mark.

The stage of eight candidates will only include one woman. But there will be six who are either governors or former governors, a U.S. senator, two who are the children of Indian immigrants, and a few multi-millionaires. 

North Dakota Gov. Doug Burgum confirmed he would be at the debate after suffering a high-grade Achilles tear in a pick-up game of basketball on Tuesday night.

Burgum is on crutches - but not on pain meds. He said he was checking with a doctor about being able to stand at the podium for the two-hour debate. He tweeted Wednesday evening: 'I'm in.' 

Meanwhile, Moderators Bret Baier and Martha MacCallum have said they will make sure Trump appears at the event - in video clips they'll show and in the questions they will ask about the former president's four indictments.

Additionally, several of the Republican candidates - such as Chris Christie and Asa Hutchinson - have vowed to attack Trump while others - like Ron DeSantis - will be wooing his supporters.

Trump will have his own counter programming on Wednesday night - a pre-taped interview with Tucker Carlson, the former Fox host whose show was canceled by the network.

And he'll have surrogates on the ground in Milwaukee for the debate. His eldest son Don Jr. and Kimberly Guilfoyle will be sitting in the debate audience and then speaking to the media after the event. 

Lake will also be in the audience. She was speaking to reporters outside the debate hall on Tuesday as Trump supporters waved signs bearing his name in the background.

'This isn't a race guys - the primary's over,' she said, citing Trump's massive lead in the polls. The former president leads by 41 points in the RealClearPolitics polling average.

She also accused Fox News of being anti-Trump, saying that is why he was skipping the debate. 

'There's no sense for him to go into this and watch a network - that has already decided they want anybody about Trump - garner ratings from him.

'He's just too smart for that. And frankly, he doesn't need that. He's already the nominee. He's so far ahead. No one can catch up.'

Rep. Marjorie Taylor Greene, another Trump ally who will be in the debate audience, told DailyMail.com it was time for the party to rally behind Trump.

'It's over. It's pointless. It's a waste of donors' money. It's just everybody needs to just get behind President Trump,' she said.

But with Trump missing from the stage, the spotlight will fall on the next two top contenders, each of whom will be standing in center stage: Florida Governor Ron DeSantis and biotech entrepreneur Vivek Ramaswamy.

Still it remains unclear whether either candidate can use the night to make up enough ground to seriously challenge Trump: the former president leads DeSantis by 41 points in the RealClearPolitics polling average and leads Ramaswamy by 49 points. 

But both DeSantis and Ramaswamy are preparing to be targets of attack. 

Running a distant second to Trump in the polls, DeSantis has set himself up as the only true rival to Trump.

'We'll be ready,' DeSantis said Monday. 'I think that with Donald Trump not being there, I don't think it's any secret that I'm going to be probably the guy that people are going to come after.' 

He told Fox News earlier this week that Trump should be there.

'Everybody should debate. Everybody has a responsibility to earn people's votes. Nobody is entitled to anything in this world, less of all the Republican nomination for president,' he noted. 

'This is really a great opportunity because I don't think very many people over the summer have been following that closely. This is going to be the first time that candidates are going to be able to speak unfiltered to a large number of Americans,' he pointed out. 

The Florida governor has been working with a top debate coach ahead of Wednesday night's event, the New York Times reported.

Other candidates are preparing for the debate with more relaxed methods. 

Ramaswamy posted a video of himself - shirtless - mashing tennis balls on Monday, calling it 'three hours of solid debate prep.' On Tuesday, he posted a video of him and his wife doing burpies. This time he had a t-shirt on.

The youngest GOP presidential contender has been targeted for his statements on foreign policy - a move that comes as he has been rising in the polls.

Nikki Haley, the former South Carolina governor and US ambassador to the United Nations under Trump, attacked him on Monday.

Ramaswamy has said he would leave Taiwan to the Chinese, he would allow Russia to keep parts of eastern Ukraine, and would curtail military aid to Israel after stabilizing the Middle East.

'This is part of a concerning pattern with Vivek,' Haley said. 'Between abandoning Israel, abolishing the FBI, and giving Taiwan to China, his foreign policy proposals have a common theme: They make America less safe.'

Haley will be the only woman on stage when the Republican contenders gather on Wednesday night and will use her experience on the campaign trail as her debate prep.

A Haley advisor told DailyMail.com: 'Nikki's been preparing for six months on the campaign trail answering unscripted questions from voters across New Hampshire, Iowa, and South Carolina. She's not afraid of the hard questions. She'll always fight for what she believes in.'

Tim Scott also has been seeing a surge in the polls lately. He's been preparing for the debate with a small circle of advisers. 

'Tim Scott will share his positive, conservative message on the debate stage in Milwaukee. This debate is another opportunity to connect with millions of voters across the country and show why Tim has faith in America and why he is the strongest candidate to beat Joe Biden,' a spokesman told DailyMail.com.

Scott is preparing for the debate by spending time with his family and his pastor, praying and going to the gym. He likes to pray from the book of Proverbs and is nearly fanatical about his workouts. 

'We view the debate not as a make or break for us,'  a source close to the campaign told DailyMail.com. 'We are not a candidate who is need of a surge or need to reset. We have the resources and infrastructure to continue going after this debate and many more.'

'We expect him to do well and he's very well prepared. But it's not a make or break moment. He doesn't need to come up with a viral one liner,' the source noted.

'He wants to share his positive and optimistic conservative message. That's what he wants to get across in the debate,' the person said. 'For a lot of voters this may be the first time to see Tim Scott.'

Mike Pence is one of the few contenders with previous experience on the national debate stage having participated in vice presidential debates.

Pence told ABC's This Week on Sunday that he is 'just going to be me' in Wednesday's debate.

'I've had a little bit of experience with nationally televised debates, but it's different with a group onstage. And look, I'm just going to be me,' he said. 'I feel like I've been preparing for this first Republican presidential debate my whole life.'

Chris Christie, who ran and failed to win the GOP nomination in 2016, also has experience having appeared in primary debates that cycle.

But he has centered his campaign on attacking Donald Trump. It's unclear how effective those attacks will be with the former president not on stage. 

He's been trying out attack lines on the campaign trail.

'By Wednesday night, the front-runner for our party's nomination is going to be out on bail in four different jurisdictions,' he said at an event in Miami. 'When are we going to stop pretending that this is normal?' 

Gov. Asa Hutchinson of Arkansas also plans to attack Trump. He said he plans to play the role of 'prosecutor' of the former president.

'I'm not going to defend Donald Trump — I will be a prosecutor,' he said in an interview with MSNBC. 'I will be telling the truth on Donald Trump, and whether he's there or not, he will be a focal point of issue.'

'Some of the candidates will be defending Donald Trump,' he said. 'I'll certainly be on the side of telling the truth. But that's a defining moment: who's going to be promising pardons.' 

Gov. Doug Burgum of North Dakota has described himself as the 'least-known candidate' on the debate stage.

He said Sunday on NBC's Meet the Press that he'll have succeeded in the debate 'if we get a chance to explain who we are, what we're about and why we're running.'