Overnight last night, ABC News projected that firearms manufacturer Pat Harrigan will be the GOP nominee in North Carolina's 10th District. He defeated more conservative Republican Grey Mills 41 percent to 39 percent. The 10th District is a solidly red seat currently represented by retiring Rep. Patrick McHenry, and Harrigan should have no trouble winning it in the fall.

—Nathaniel Rakich, 538

Last night, the "uncommitted" campaign made headway in a few more states. After a protest vote for Biden's response to Israel's war against Gaza helped net over 100,000 uncommitted votes in last week's Michigan Democratic primary, supporters of the Listen to Michigan campaign expanded their efforts to other states with "uncommitted" or similar language as an option on primary ballots.

With 89 percent of the expected vote reporting, 19 percent of Democratic primary voters in Minnesota voted uncommitted, eclipsing the 13 percent reached last week in Michigan. That means "uncommitted" will send at least 8 (and up to 11) delegates from Minnesota to the Democratic National Convention in August, per the latest ABC News projections.

"No preference" also garnered 13 percent of ballots cast in North Carolina and 9 percent in Massachusetts, while 8 percent of primary voters in Colorado chose "noncommitted." However, those aren't enough to meet their respective states' thresholds to send a delegate to the national convention. (That's 15 percent in all three of those states.)

—Irena Li, 538

While Haley called on Trump to earn Republicans' votes, Mitch McConnell suggested that he already has. "It is abundantly clear that former President Trump has earned the requisite support of Republican voters to be our nominee for President of the United States," McConnell said in a statement. The rest was pretty standard endorsement fare, going on to tout Trump's accomplishments on tax reform and judicial appointments, and criticizing Biden.

It's an undramatic end to the minor drama over whether the soon-departing majority leader would endorse Trump, with whom he's undoubtedly had a rocky relationship. In the end, McConnell waited until just after Trump's final major opponent dropped out to fall in line. With one of the last major (potential) party holdouts in his corner, the general election train is in full swing for Trump.

—Tia Yang, 538

According to the latest numbers from our colleagues at ABC News, Trump has 1,051 of the 1,215 delegates he needs to mathematically clinch the Republican nomination for president. Haley's withdrawal from the race puts him on track to reach that magic number next Tuesday, March 12. A total of 199 delegates will be allocated between now and then, and presumably Trump will win all or almost all of them.

—Nathaniel Rakich, 538

Super Tuesday has over 40 years of history that are deeply entwined with a bunch of issues in the presidential nomination process. The term "Super Tuesday" was first used in 1980 but was promoted by Democrats in 1988 as a deliberate effort to give an advantage to more moderate candidates. This was a direct reaction to the idea that the party's 1984 nominee, Walter Mondale, had lost to Ronald Reagan because he was too liberal. This strategy didn't really work out, though, and Democrats ended up nominating another northern liberal, Michael Dukakis.

In other words, this early attempt at a Super Tuesday brought some of the disadvantages of a regional primary, reducing the amount of attention on individual states and pressuring states to move their primaries earlier without really strengthening the influence of the region. Another drawback was that, by trying to enhance Southern influence by holding contests early, Super Tuesday also contributed to the "front-loading" problem", or the issue of having too many delegates selected at the beginning of the primary calendar.

Over time, Super Tuesday has taken on other significance as an important turning point in the race. As party politics scholar Caitlin Jewitt noted, in 2016, everyone thought that Sen. Ted Cruz needed to do well on Super Tuesday, which was heavily concentrated in Southern states where he needed to rack up wins — and when that didn't happen, it was a significant blow to his candidacy. For Biden in 2020, Super Tuesday marked the point when the party consolidated behind him. And in 2008, Super Tuesday made it clear that the Democratic nomination was a real race between Hillary Clinton and Barack Obama, as neither one scored a decisive victory.

It's hard to know exactly how this will play out in 2024. Republicans don't have the same ideological history with the big primary day as Democrats do. But the potential for a turning point in the race is there: Because so many delegates are at stake today, unless Haley wins a significant share of them, it may not make sense for her to stay in the race after tonight.

—Julia Azari, 538 contributor