At PolitiFact, this is our fifth presidential cycle. We’ve published more than 23,000 fact-checks since launching in 2007, all using our Truth-O-Meter, which rates claims on a scale from True to Pants on Fire false for the most ridiculous claims.

If PolitiFact is new to you, there are a couple of rules of the road.

First, we don’t fact-check every claim every candidate says. We couldn’t … we’d be dead.

We focus on claims that are particularly interesting, in the news or obviously potentially wrong. Our grading scale tries to measure both the literal truth and how voters might interpret a politicians’ words. So if Pence tonight claims that he and Trump “achieved energy independence” in their first three years in office, it can be more complicated to fact-check than you think.

In Pence’s case, yes, the United States did produce more energy than its citizens consumed during the Trump/Pence White House, but that was built on more than a decade of improvements in shale oil and gas production, as well as renewables. And the U.S. did not produce more gasoline than it consumed (which is maybe what you were thinking about). And if that’s not enough, even though the U.S. didn’t use all the energy it produced, it still imported a substantial amount of energy to serve domestic markets.

So far in this cycle, we’ve published 52 fact-checks of the GOP candidates. Our checks tend to follow the polling of the race. We’ve fact-checked Trump 17 times, DeSantis 14 times, Pence six times, Haley and Tim Scott each five times, and so on. We'll be drawing on those previous fact-checks, as well as the thousands of other claims we've vetted, throughout the night.

-Aaron Sharockman, PolitiFact

I flew to Milwaukee earlier this week to talk to some local voters and learn more about why the GOP decided to have its first presidential debate of the 2024 cycle in the state.

-Analysis by Galen Druke of FiveThirtyEight

DeSantis remains Trump’s closest challenger, but his support has been dropping over the past several months: He currently trails the former president by nearly 40 percentage points in our national polling average.

With that drop have come some shake-ups in the DeSantis campaign. The campaign has laid off around one-third of its 92-person staff, with the latest cuts coming in July, according to ABC News. Changes stretched all the way to the top: DeSantis replaced his campaign manager with his governor’s office chief of staff. On top of that, some of his top donors have voiced concerns, saying they want DeSantis to recruit more major donors and take a more moderate approach on social issues.

All of that has made this debate crucial for DeSantis, both in terms of trying to chip away at Trump’s lead and proving to his supporters that he actually has a shot. He’s recruited a veteran debate coach and is getting advice from a supportive super PAC, according to The New York Times. That advice? Rather than attack the front-runner, DeSantis should “take a sledgehammer” to Ramaswamy who, unlike DeSantis, is rising in the polls. DeSantis won’t just be trying to win the debate tonight: He’s also aiming to push back against the rolling tide of news that hints at a flailing campaign.

-Analysis by Monica Potts of FiveThirtyEight

DeSantis and Ramaswamy, both newcomers to the presidential debate stage, will appear front and center on Wednesday night.

That's because where candidates will stand was determined by how they are faring in the polls.

More seasoned politicians, such as Pence or Christie, have been placed closer to the outer rim because of their more middling numbers so far. Hutchinson and Burgum will stand on either end.

-ABC News' Alexandra Hutzler

As Republican candidates gear up for the debate, many have specific rituals they’ll be doing in preparation.

A campaign adviser for Haley said she will be listening to music, “lots and lots of music: Joan Jett, Queen, Def Leppard and [the] Go-Gos, to name a few.”

DeSantis has spent today with his wife, Casey, and their three children, though a campaign spokesman offered few details about how the family has spent their time.

Hutchinson posted a photo of himself preparing with notepad and laptop in hand.

“Some last minute studying and prep for tomorrow! It’s important to show up and be ready to answer the tough questions, you deserve nothing less than a leader ready to lead on day one,” Hutchinson captioned the photo online.

Pence will plan to spend time in prayer before the debate, while Scott took a tour of the debate stage, which he posted a video of, along with encouragements from his family, to X, formerly known as Twitter.

Others prepared physically, earlier this week.

Ramaswamy posted videos to X of himself playing tennis and him and his wife doing floor exercises in a gym throughout the lead-up week.

Burgum was playing a stress-relieving pickup game of basketball on the eve of the debate, according to a campaign press secretary, when he sustained an Achilles injury that called into question his ability to participate in the event.

He will be participating, albeit on crutches, per a photo posted to his X account.

-ABC News’ Gabriella Abdul-Hakim, Libby Cathey, Abby Cruz, Will McDuffie and Olivia Osteen