In the past decade or so, Iowa has gone from a competitive state in general elections to a reliable Republican stronghold. Trump won the state by eight percentage points in 2020, a wider margin than Barack Obama’s (six points) in 2012. Once represented by a split-party Senate delegation — Republican Chuck Grassley and one-time presidential hopeful Democrat Tom Harkin — Iowa has been represented by two Republicans, Grassley and Joni Ernst, since 2015. And as of last year, Republicans also control all four of the state’s House seats, representing Iowa’s first all-GOP congressional delegation since the 1950s. While no one really expects Biden to win there in 2024, Barack Obama won the state twice, and so did Bill Clinton. Iowa was even one of the few states won by Michael Dukakis in 1988!

There are many possible reasons for this transformation, but changes in Iowa appear to be part of a larger shift in rural parts of the upper Midwest — North and South Dakota, as well as northern Wisconsin and parts of Minnesota, have also become more Republican over the past decade. One piece of the story is the decline of rural Democrats who used to represent these places, often with a populist bent and a focus on agricultural issues, though that may be a chicken-and-egg conundrum — it’s not clear what’s causing what. The resonance of Trumpism with rural and Midwestern voters is also important. But here’s where Iowa politics has a twist: While Trump is the favorite to win the caucuses, his status among Iowa Republicans has been in question. Gov. Kim Reynolds has endorsed Ron DeSantis and so has prominent evangelical leader Bob Vander Plaats. Iowa’s turn to the right is a Trump-era development, but it appears to go beyond Trump.

Happy Iowa caucuses night! I’m Julia Azari, a political science professor at Marquette University in Milwaukee, Wisconsin, and I’m delighted to join 538 for a third presidential primary season. I study U.S. political parties, the American presidency and political communication. For me, the Iowa caucuses are all about the expectations and the post-contest spin, so I’ll be looking at how candidates perform relative to expectations, and the stories we hear in the news about what it means for the remaining candidates in the race.

When you think of a political campaign, you probably think about a candidate speaking to voters in an intimate church basement, or shaking hands in line at a coffee shop. The GOP presidential candidates have held hundreds of such events in Iowa, and, with the help of ABC News reporters on the ground, our indefatigable research team has collected data on who has held the most campaign events in the Hawkeye State (through yesterday).

By far the busiest campaigner has been Ramaswamy, who has held 332 events in Iowa since he announced his campaign. He also claims to have visited all 99 Iowa counties — a feat dubbed the "full Grassley" after Sen. Chuck Grassley — twice! By comparison, the second-busiest campaigner has been DeSantis, and he has held "only" 160 events since he jumped in the race.

Ironically, the active candidate who has held the fewest events in the state is Trump, who has held just 36. Yet he’s probably going to win the state tonight — more evidence for political-science studies that have found that campaign events don’t actually make that much of a difference.

Although Trump emerged as the Republican nominee in 2016, he got off to a slow start in Iowa. In that year’s caucuses, Trump narrowly came in second behind Texas Sen. Ted Cruz, receiving 24.3 percent of the vote compared to Cruz’s 27.6 percent, while Florida Sen. Marco Rubio finished in a close third with 23.1 percent. The crowded candidate field and highly-competitive contest produced a messy map, with Cruz and Trump tending to do better in places with fewer four-year college graduates — often more rural areas — and Rubio doing comparably better in the state’s more well-educated population centers.

It was a competitive start to a primary that was fraught with uncertainty from the jump. While competitive primaries aren't unheard of, in the modern presidential primary era (which starts after the reforms that stemmed from the 1968 election), party elites and insiders have been largely successful at putting their thumb on the scale, a political science theory known as "the party decides." In brief, the theory holds that the preferences of party elites, rather than those of rank-and-file primary voters, are decisive in determining the party's nominee. More specifically, party elites have already exerted their influence through endorsements to effectively anoint a nominee by the time voting contests even begin.

The 2016 GOP primary represented a break from that trend, though, because Republican elected officials were slow to endorse a candidate, which some characterized as the party failing to decide. Ahead of the Iowa caucuses, Trump had received zero endorsements from sitting members of Congress or governors, but Cruz, Rubio and the other contenders weren't raking them in, either — and in that vacuum, Trump was able to build momentum. In this context, Iowa's close result seemed to be a microcosm of that high level of uncertainty.

While Iowa's results seemed to throw cold water on Trump's early momentum, he may not have been the most intuitive candidate given the state's demographics. It's largely known that Iowans take their winnowing role in the primary process seriously, but the state's primary hasn't picked the eventual Republican nominee since 2000. More reliably, Iowans since then have picked the candidate most closely associated with the religious right (like Rick Santorum in 2012, and Mike Huckabee in 2008), because evangelical voters are a strong voting bloc there. In 2016, that bloc was decidedly behind Cruz.

This time, despite concerted efforts by DeSantis to court evangelical voters, Trump won't have that issue. The evangelical vote in Iowa, and beyond, is now fully in Trump's corner. And with the party establishment also seemingly lining up behind him, it's no wonder he's seen as an overwhelming front-runner this evening.