Haley took the stage in a bright red dress and in front of a row of American flags just after 10 a.m. from South Carolina, and announced she was suspending her presidential campaign. She began with a retrospective of the start of her campaign, and reiterated her conservative principles, including a low national debt, a small federal government and the need to promote democracy worldwide by standing by America's allies. With that, the final Trump challenger is out of the race, and Trump is the presumptive nominee, a fact Haley acknowledged.

Like most major candidates who ran for the Republican nomination, other than Trump, Haley had previously signed the RNC's pledge to support the eventual nominee, but she's distanced herself from that pledge a bit recently. Haley didn't endorse Trump this morning, but she did congratulate him, while slightly criticizing the way that he's run his campaign. "We must turn away from the darkness of hatred and division," she said. She went on to say that Trump needed to bring people into his cause, saying, "It is now up to Donald Trump to earn the vote of those in our party and beyond it." Haley has noted in previous speeches that she's captured a sizable portion of the vote in some states, even winning Washington, D.C., and Vermont, signaling that some Republican voters are dissatisfied with the former president as a choice for the future.

In the end, as Meredith noted, she made a somewhat rare reference to the historic nature of her campaign. She's the first Republican woman win any state's nominating contest, and she noted that her mother, a first-generation immigrant, had gotten to vote for her for president in South Carolina. She directed her final lines, quoting from the Book of Joshua, to women and girls who had watched her campaign.

—Monica Potts, 538

Back in late January, we wondered if the 2024 Republican presidential primary might be the shortest in modern history. But because Haley continued to contest the race until Super Tuesday, the competitive period of this year's GOP contest ended up falling short of setting any records. Still, it was undoubtedly on the quick side, historically.

The 2024 Republican race lasted 52 days from Iowa through today, during which time all states and the District of Columbia held 25 contests. The March 6 effective end date puts it just behind the record earliest end of a nomination season (March 3 in the 2004 Democratic contest) and the number of state-level elections (19 in the 2000 Democratic race). Nonetheless, going back to the 1976 election cycle, this year's Republican campaign was much shorter than the median number of competitive days (85 days), state-level contests (39) and end date (April 9).

To be clear, measuring the effective end date of a nomination race's competitive period is not always cut and dry, although it was this time around. We based our approach on political scientist Caitlin Jewitt's work on presidential primary competition, which classified a candidate as their party's presumptive nominee either when all viable opponents have dropped out or when they clinch a delegate majority from the results of primaries and caucuses. In Trump's case, Haley was his last viable opponent.

—Geoffrey Skelley, 538

This morning, as Haley was dropping out, Trump sent a message over his social media platform Truth Social reacting to the results:

"Nikki Haley got TROUNCED last night, in record setting fashion, despite the fact that Democrats, for reasons unknown, are allowed to vote in Vermont, and various other Republican Primaries. Much of her money came from Radical Left Democrats, as did many of her voters, almost 50%, according to the polls. At this point, I hope she stays in the "race" and fights it out until the end! I'd like to thank my family, friends, and the Great Republican Party for helping me to produce, by far, the most successful Super Tuesday in HISTORY, and would further like to invite all of the Haley supporters to join the greatest movement in the history of our Nation. BIDEN IS THE ENEMY, HE IS DESTROYING OUR COUNTRY. MAKE AMERICA GREAT AGAIN!!!"

—Nathaniel Rakich, 538

In her short remarks, Haley quoted Margaret Thatcher: "Never just follow the crowd. Always make up your own mind." She used this quote to encourage the likely nominee, Trump, to appeal to the primary voters who he hasn't won over. She also thanked the girls and women who have supported her campaign, as another (subtle?) reminder of her historic run.

—Meredith Conroy, 538 contributor

On Sunday, Republicans in Washington, D.C., voted for Haley by nearly 30 percentage points in the GOP's party-run primary, giving her all 19 national delegates from the nation's capital. This marked her first victory anywhere in this year’s primary contest, and the first ever primary or caucus victory for a woman in the history of Republican nomination races. Yet the other contests that took place just ahead of Super Tuesday otherwise showcased Trump's strong hold over his party's base. This included victories on Saturday in caucus-convention races in Idaho, Michigan and Missouri, and in North Dakota's Republican caucuses on Monday.

In Michigan, Republicans gathered at Saturday's state party convention to allocate 39 national delegates from the state’s 13 congressional districts (three per district). The voters consisted of precinct delegates mostly elected at the August 2022 state primary as well as Republican elected officials, and they handed Trump all 39 district-level delegates. This result brought Trump's Michigan haul to 51 of the state's 55 delegates, after he had already won 12 of its 16 at-large delegates in the Feb. 27 primary.

The Michigan GOP's split primary-caucus approach came about in part because national Democrats added Michigan to the early part of their presidential primary calendar, prompting the Democratic-controlled state government to shift the state’s primary date into late February. Since the new date violated the national GOP's calendar rules, Michigan Republicans used a workaround whereby the primary results would allocate the state's at-large national delegates, but the state party didn’t formally make the allocation until March, at Saturday’s caucus-convention that also allocated district-level delegates.

Trump also swept caucuses in Idaho and Missouri on Saturday, and then North Dakota on Monday. In Idaho, Trump won 85 percent of caucusgoers, easily surpassing the state's 50 percent winner-take-all threshold to capture all 32 of Idaho's national delegates. In Missouri, Trump won every state- and congressional district convention delegate elected at local caucuses around the state, all but guaranteeing that he will sweep all 51 national delegates when the district and state conventions formally allocate delegates in April and May, respectively. And in a near-repeat of Idaho, Trump won 84 percent of caucusgoers in North Dakota on Monday to claim all 29 of the state’s national delegates.

—Geoffrey Skelley, 538