ABC News can now project that Trump will win the Colorado primary. With almost half the expected vote reporting already, Trump has 60 percent to Haley's 36 percent. It's Trump's eighth win of the evening already, and this one is particularly rough for Haley, as this was one of the few states where she had the best shot at an upset win.

—Nathaniel Rakich, 538

Polls have now closed in Minnesota, which was a sleeper battleground in the 2016 general election, but tends to support Democrats. There are a greater-than-average number of college graduates in the state, which should be good for Haley, but there's also a sizable white working class population, which, if you're reading this live blog, you probably already know, is good news for Trump.

—Jacob Rubashkin, Inside Elections

In one of the least surprising developments of the night, ABC News projects that Trump will win Alabama. Only 5 percent of the expected vote has reported there, but Trump leads Haley by a punishing 69-point margin, 83 percent to 14 percent. We expected Alabama to be one of Trump's strongest states, and that looks to be the case.

—Geoffrey Skelley, 538

Going into tonight, I thought that Colorado could be a dark horse state for Haley. There wasn't a single poll of the race there, and the state's highly educated demographics seemed like a good fit for her.

Well, so far, it ain't happening. With 28 percent of the expected vote reporting, Trump is taking 57 percent of the vote there, while Haley has just 40 percent.

—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