Okay, maybe I'm biased because it was my assignment to report out some of the downballot races tonight, but when the presidential primaries are basically all over but the cryin', they make for much more interesting politics. But once Biden and Trump make it official, don't let the intensity of the presidential race overshadow these races further down the ballot. There's a lot at stake — majority powers in two narrowly divided chambers! — and these races can sometimes tell us more about what voters think is important than the marquee race at the top of the ticket. Of course, you can always depend on 538 to keep you up to speed!

—Kaleigh Rogers, 538

With the exception of a remarkable outcome in American Samoa, this was a night without very many surprises. Trump and Biden continue to dominate their respective parties, even as doubts linger — about age, about policy and about electability, to name a few concerns. But Trump's main opponent, Haley, has just won her second primary of the season — Vermont. Biden has opposition on the left, but no challenger; from the center of his party, he has a challenger, but no clear opposition.

One lesson from all of this is that even for candidates with as many liabilities as these have, it is incredibly difficult to compete with the name recognition and influence of a sitting or former president. In theory, parties could opt to nominate someone other than the sitting president — in practice, they have not really done so since the mid-19th century. Parties have come to be defined by their presidents. We especially see this with Trump, but this primary season and Super Tuesday have highlighted just how much it's true of Biden, too.

And yet it shows the cracks in the presidential dominance of their parties as well. Even as Trump has largely taken over the GOP, there remains a consistent, if small, segment that would like to see the party move in a different direction. And even as Biden continues to (almost) sweep the primaries, activists are organizing to use the primaries to protest some of his policies. Still, it's telling that ultimately these intraparty disagreements aren't framed as fights between factions, but rather in terms of support or opposition to the presidential figure at the head of the party.

—Julia Azari, 538 contributor

We're not ending the live blog just yet since there are more results to come ... But we're going to get some shuteye and be back here tomorrow, bringing you updates from some of today's later-closing races.

So, it's "final" thoughts time — what did everyone take away from tonight's results?

—Tia Yang, 538

Interesting, Geoffrey. I was expecting Carl to win that one, as he had the geographic advantage: Carl and Moore were thrown together into this new district in redistricting, and Carl represented 59 percent of residents in the new district. But perhaps Moore’s conservative bona fides carried the day: He is a member of the House Freedom Caucus, so this primary was a victory for the insurgent wing of the Republican Party.

—Nathaniel Rakich, 538

Tonight, I'll be paying close attention to the results coming in from Alabama's GOP presidential primary.

That's not because there is much doubt about the outcome. Against stiffer competition in 2016, Trump carried every county in this Republican-dominated state, winning by 22 percentage points statewide. In 2024 primaries so far, Trump has tended to do well not only in places where he did well eight years ago, but also in places where Ted Cruz, the leading candidate among more conservative and evangelical voters, did well. Since Cruz finished second in Alabama in 2016, it's not a very promising state for Haley.

But even without much question about who's going to win statewide, Alabama serves as a bellwether for the state of today's Republican Party. It's the state with the highest population share of evangelical Protestants nationwide, a focal constituency of the contemporary GOP. Alabama has also been home to several competitive GOP primaries in recent years that can jointly tell us a lot about competition in the party today. Even after Trump's rise to the top of the party in 2016, precinct-level returns in Alabama's Senate primaries make clear that there aren't consistent pro-Trump and anti-Trump blocs going head-to-head in election after election. Instead, GOP candidates in recent Alabama primaries have put together somewhat idiosyncratic geographic coalitions.

Consider 2017, when appointed U.S. Senator Luther Strange, who had the backing of both Trump and the GOP establishment, competed against judge Roy Moore in a special election for the GOP's Senate nomination. Despite accusations of child sexual abuse, Moore prevailed over Strange in the primary (before losing to Democrat Doug Jones). New research suggests that in that primary, precinct-level support for Moore was higher in places where Trump and Ben Carson had done better in 2016, but the correlations are pretty modestly sized. In other words, knowing where Trump did better in 2016 really didn't have much predictive power in the next year. Still, Marco Rubio's 2016 vote share was negatively associated with Moore's, meaning those two candidates drew support from different places.

2020 may provide a clearer test: Trump's first supporter in the U.S. Senate and subsequent attorney general, Jeff Sessions, was running to take back his old seat, but Trump and Sessions had since fallen out and Trump instead endorsed the eventual winner, Tommy Tuberville. The places that had backed Trump in 2016 were somewhat less supportive of Sessions in 2020. Still, these correlations were pretty modest, and Trump's 2016 support also wasn't strongly correlated with backing either of Sessions's major opponents, Tuberville or Bradley Byrne.

And in the 2022 Republican Senate primary, Trump support was slightly negatively associated with 2022 support for both Rep. Mo Brooks, the conservative whom Trump unendorsed during the campaign, and eventual winner Katie Britt, who he did endorse. Trump's 2016 vote was only somewhat positively correlated with support for Mike Durant, a helicopter pilot who was shot down in Somalia as part of the battle depicted in "Black Hawk Down." But like 2017 and 2020, the 2022 Republican primary was not just a rerun of 2016.

Now, with Trump himself on the ballot, it's a different story. I expect that Trump will do very well in the parts of Alabama that he dominated in 2016 (read: most of the state), and that Haley's vote margins will be slightly stronger around Birmingham and Huntsville, just as Rubio did eight years ago. This was true in New Hampshire, for example, where Trump's 2016 precinct-level vote share was correlated with his 2024 vote share at 0.63, a strong correlation given the very different competition he faced in the two years. But, as a close look at Alabama primaries in recent years shows, Trump's 2016 supporters haven't necessarily formed a cohesive voting faction. During the Trump era, when Trump is not on the ballot himself, voters haven't always hewed closely to the divisions he has fostered.

—Dan Hopkins, 538 contributor