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

Voters are choosing more than their parties' presidential nominees tonight. In five Super Tuesday states, they're also deciding on candidates for statewide and local offices. Several consequential judicial elections are being held tonight, for positions on state supreme courts in Alabama, Arkansas and Texas, and on the Criminal Court of Appeals in Texas.

In Arkansas, nonpartisan general elections are being held to fill two vacancies on the Supreme Court, creating a game of musical chairs among the sitting justices that could potentially accelerate the already-conservative court's rightward shift. Chief Justice Dan Kemp is stepping down, and three of the four candidates running to replace him are already sitting on the court, while another sitting justice is angling to move to a different open seat on the court. The shuffle could leave two vacancies that would allow conservative Gov. Sarah Huckabee Sanders to name replacements to finish their terms.

Alabama's Supreme Court Chief Justice Tom Parker, who recently made waves nationally with a ruling that frozen embryos used for IVF are children, is also retiring because of the state's mandatory retirement age. Two candidates are running for the Republican nomination to replace him: sitting Associate Justice Sarah Stewart (who had to give up her seat to run for the top slot) and former state Senator Bryan Taylor. While Stewart joined the 8-1 majority opinion in the IVF case and both candidates have defended the decision, Taylor has claimed that Stewart is the "most liberal" justice on the all-Republican court, and received a huge influx of outside spending from conservative anti-abortion group Fair Courts America. Whoever wins will likely face (and defeat) Democrat Greg Griffin>) in the general election.

In Texas, Supreme Court Justice John Devine is facing a primary challenger who has questioned his ethics, but a bigger political feud is playing out in other races. Allies of Republican Attorney General Ken Paxton are funding primary challengers to three Criminal Court of Appeals judges who ruled against him in a voter fraud decision, limiting his power to prosecute those cases. And as Nathaniel noted earlier, Paxton, who had been accused of abusing power to protect a political donor, has also endorsed primary challengers against 34 of the 60 Republican legislators who voted to impeach him last year.

—Monica Potts, 538

NASA astronauts Jasmin Moghbeli and Loral O'Hara voted in today's primaries ... from outer space. The two have been orbiting the earth aboard the International Space Station for roughly six months, but both still found a way to exercise their civic right.

—Cooper Burton, 538

Four years ago, Super Tuesday was one of the last big news events before the declaration of the COVID-19 pandemic. Just days later, the U.S. and much of the world would go into lockdown in an effort to stem the virus's spread.

As Julia noted, in 2020, Super Tuesday marked the point when the Democratic Party consolidated behind Biden. But I think that, partly because of the pandemic, even close observers of American politics don't appreciate just how unlikely Biden's Super Tuesday comeback was.

This year in Iowa, Ron DeSantis's second-place finish with 21 percent of the vote was enough to effectively end his campaign. But in 2020, Joe Biden came in fourth in the Iowa Democratic caucuses.

Similarly, pundits have viewed Trump as the prohibitive favorite in the 2024 race since at least his New Hampshire victory, when he topped Haley 54 percent to 43 percent. In 2020, however, Biden's New Hampshire performance was far weaker than Haley's this year — he finished fifth in the state, winning just 8 percent of Democratic primary voters.

But in a very short period four years ago, Biden resurrected his campaign. He convincingly won South Carolina on Feb. 29 thanks to his strength with Black voters, who had been few and far between in Iowa and New Hampshire.

Then, both Amy Klobuchar and Pete Buttigieg endorsed Biden in the run-up to Super Tuesday, consolidating the more moderate side of the Democratic Party against Bernie Sanders. That, in turn, positioned Biden for a decisive Super Tuesday win that made him the front-runner in short order. While Sanders won California, Biden won 10 states, including Massachusetts, North Carolina and Texas.

What explains the dramatic change in Biden's fortunes over a few short days leading up to Super Tuesday in 2020? In his book "Learning from Loss," political scientist Seth Masket emphasizes the Democrats' overwhelming aim to defeat Trump, and to find a candidate who gave them the best chance of doing so. At the time, there was evidence that Biden ran better against Trump than other Democrats. Many Democrats were willing to follow the cues of party leaders about their most competitive candidate, and in doing so, they vaulted Biden to the nomination.

In this year's GOP primary, there's some evidence that Haley may be a stronger general election nominee than Trump. But in a late-November survey I conducted via YouGov, GOP voters overwhelmingly saw Trump, not Haley, as their strongest candidate, and there's no evidence that's changed. So on the Republican side, the grounds for a similarly sudden Super Tuesday switch just aren't there.

—Dan Hopkins, 538 contributor