The Iowa caucuses are today. Here's what you need to know

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Republicans in the Hawkeye State convene Monday on a potentially record-breaking chilly night — that will likely affect turnout — to commence the presidential contest for 2024.

The caucuses are the first chance for Republican voters to weigh in on who they want to be their nominee. It will be a first test of former President Donald Trump's hold on the GOP base. He leads overwhelmingly in polls for Iowa and nationally, as he faces 91 criminal and civil felony charges — including for actions he took as president related to the Jan. 6 insurrection.

The stakes are high. Here's what to watch out for:

• The margin of victory: Trump has been leading in the polls by historic margins in Iowa, an average of 34 points currently. The largest win ever in the GOP Iowa caucuses was 12.8 points. What is Trump's margin of victory, if he wins? 

• The order of finish: Florida Gov. Ron DeSantis has been in second place for the entirety of this campaign, but former Trump U.N. ambassador Nikki Haley has now crept up past DeSantis narrowly, within the margin of error. That correlates with Haley and groups supporting her bypassing DeSantis and allies in their ad spending in Iowa. DeSantis needs to finish second and outperform where he's been polling to have a rationale to continue his campaign.

• The weather: With a forecast set for a sub-zero high, the inclement weather will likely greatly affect turnout. Trump is relying on first-time caucusgoers, as he did in 2016 when he lost Iowa narrowly. He has a much better ground game in Iowa this time around, but there's only so much you can do in those kinds of conditions.

Here's what you need to know about the caucuses:

What time do the caucuses take place?

They begin at 7 p.m. CT (8 p.m. ET) and will last roughly an hour. Caucusgoers write down their candidate of choice. In past years, depending on the size of the caucus, this could have been done through a show of hands. Votes are then tallied in front of caucus attendees and campaign representatives to be submitted to the state party.

Who can vote?

Only registered Republicans can vote, but few of them do. The GOP turnout record is 186,000 set in 2016. That's only about 25% of total registered Republicans in the state.

But the weather could greatly affect this.

Where do the caucuses happen?

They'll take place in 1,657 precinct locations across all 99 counties in the state, in spaces including libraries, churches and school gymnasiums.

The caucuses will determine how 40 delegates are selected for the party's national convention later this summer. Iowa will receive 2% of the total party delegates, and those delegates will be allocated proportionally.

What about Iowa Democrats?

Democrats will also be caucusing, but they won't cast votes for president at them this year. Instead, they'll send mail-in ballots over the next few weeks, which the party will tally up by March 5 — releasing the state's primary results well after South Carolina's race in February. The reshuffling in the Democratic National Convention nominating calendar comes after calls for a state that is more demographically representative of the country go first. Plus, the race won't be as competitive since there aren't any major challenges to President Biden's bid for reelection.

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