Primary Season Is (Finally) Over. Here Are 5 Things We Learned.

Primary season is over: Democrats and Republicans have chosen their standard-bearers and defined their major arguments, and the general election has begun.

The midterm campaigns will not only determine the balance of power in Congress and the states, but also shape the strategies and identities of the two parties heading into the 2020 presidential race.

Here are some of the main lessons we’ve taken from the primaries and the start of the fall campaign.

Democrats hope to use the midterm elections to position themselves for a comeback in the 2020 presidential election, by retaking or capturing two swaths of the country President Donald Trump carried in 2016: the industrial Midwest, stretching from Wisconsin to Pennsylvania, and the diverse Sun Belt battlegrounds of Florida, Arizona and Georgia.

They have nominated starkly different sets of candidates in the two regions, representing two broad paths forward for the party. In the Midwest, the party has largely fielded well-known white politicians who are modestly to the left of center — figures like Richard Cordray, the former bank overseer in the Obama administration who is locked in a close race for governor in Ohio; and Gretchen Whitmer, the former Democratic leader in the Michigan state Senate who is leading in the governor’s race. These candidates are seeking to reassemble the traditional, union-heavy Rust Belt Democratic coalition that frayed badly in 2016.

The Democratic tickets in the Sun Belt are more diverse and more liberal, led by candidates such as Andrew Gillum, the progressive Tallahassee mayor who seized the nomination for Florida governor in an upset; David Garcia, a professor-turned-activist challenging Gov. Doug Ducey in Arizona; and Stacey Abrams, the former Democratic leader in the Georgia House. All three candidates are counting on mobilizing voters who have not typically turned out in midterms, to transform these Republican-leaning states into purple swing states before 2020.

Democrats are likely to gain across both regions, overall. But if they fare markedly better in one than another, it could heavily shape Democrats’ thinking about 2020 and bolster either the primary candidates more focused on mobilizing Democrats or those determined to win back Trump voters.

A record number of women emerged from primary elections this year, powered by strong turnout among female voters and an apparent hunger across the electorate for candidates promising change. There are 257 women running for House and Senate seats around the country — 197 of them Democrats — and more than a dozen female nominees for governor. This class of candidates has the potential to create a dramatic change in the image and culture of U.S. government.

On the Democratic side, the appeal of female candidates appeared to transcend ideological fault lines in the party. Democrats nominated liberal women and moderate women, military veterans and activists, corporate lawyers and Bernie Sanders organizers. They nominated women who worked for Hillary Clinton’s historic presidential campaign, and women who pledged never to help Nancy Pelosi, the barrier-breaking former House speaker, reclaim that job.

Polls suggest the country is headed for a gaping gender gap in November, as moderate women flee the Trump-led Republican Party but white men remain mostly loyal. That could set up a powerful contrast in the new Congress between an incoming class of female lawmakers, and a president who has been accused by numerous women of serious sexual misconduct. And it could send a clear signal about the kind of leader Democrats want in 2020.

Republican candidates jockeyed to see who could hug Trump tighter in this year’s primaries, while Democratic hopefuls veered to the left in a series of nominating contests. But even as the two parties seem to be pulling farther apart from one another, it was what they had in common this primary season that illustrates how much politics is being transformed: Republicans and Democrats in 2018 paid little heed to the decorous rules and precedents that have long governed how they choose candidates.

Trump ran through the Republican primaries, shredding the tradition of presidential neutrality by taking sides in nominating contests and even opposing a handful of incumbents. His interventions largely pleased Senate Republicans, who kept him out of some races and prodded him into others. But his endorsements in governor’s races blindsided the party and in some cases may have propelled weaker general election candidates.

For their part, a group of Democratic insurgents targeted incumbent lawmakers who had no whiff of scandal and reliably liberal voting records. And incumbency, corruption-free service and voting the right way did not prove sufficient for Reps. Joseph Crowley of New York and Michael P. Capuano of Massachusetts, who were upset by women of color, Alexandria Ocasio-Cortez and Ayanna Pressley, who argued that this moment demanded something more.

The question now is whether 2018 represented a Trump-era anomaly — a norm-defying president and a radicalized opposition party — or the start of a new, less genteel primary culture.

The Republican House majority is beleaguered, burdened by Trump’s intense unpopularity and battling an imposing set of Democratic challengers with broad appeal. But at the outset of the general election, there is no more urgent problem for the party than the dozens of open seats Republicans must defend, where long-serving incumbents chose to retire and the party has struggled to field strong replacements.

Democrats must gain 23 seats to take control of the House, and they could win a quarter or more just from these vacancies. Democrats might have struggled to beat Rep. Dave Reichert in the Seattle suburbs or Rep. Frank LoBiondo in southern New Jersey, and it could have been impossible to defeat Rep. Ileana Ros-Lehtinen in Miami. But all three incumbents retired, and their seats are now tossups or leaning toward the Democrats.

There are similarly endangered open seats in most parts of the country, including rural Kansas, Southern California and the suburbs of Philadelphia. The challenge extends to the Senate, too, where Democrats have a slim-but-plausible pathway to taking control in large part because Sen. Bob Corker of Tennessee decided to retire and former Gov. Phil Bredesen, a popular moderate Democrat, entered the race to replace him. (He faces Rep. Marsha Blackburn.)

Republicans may yet keep their control of the House, with a powerfully funded, overwhelmingly negative campaign aimed at disqualifying Democratic challengers in swing seats. But their margin for error is slim.

With strategists in both parties increasingly convinced Democrats are well positioned to take control of the House, the center-stage drama this fall may be the battle for the Senate majority. And unlike in the House, no Senate Democrats were denied renomination or, more to the point, faced much in the way of a challenge at all from the left.

So with the Senate election this year mostly being fought in conservative-leaning states that Trump carried in 2016, this turn of events has created an odd juxtaposition: The full success of the anti-Trump forces in the midterms could hinge on Senate Democratic candidates who spend more time discussing how they can work with the president than they do vowing to block his agenda.

From North Dakota and West Virginia to Tennessee and Arizona, Democratic candidates for the Senate are benefiting from their party’s disdain for Trump, raising money from all over the country and welcoming a new wave of motivated activists to their campaigns. But they are downplaying their objections to his presidency in a way that makes clear that they do not think red America is fully embracing the #resistance.