The red parts got redder and the blue parts bluer in a midterm election that underscored America’s deep divide

Reporting from Washington —  Democrats owe their newly elected House majority to an upsurge of votes from women, younger Americans and white college graduates, deepening divides that emerged in the election two years ago and shaping the debate within the party over how to challenge President Trump in 2020.

With more than a dozen races left to be called, including several in California, Democrats appear to have picked up a net of about 35 congressional seats, significantly more than the 23 they needed for a majority.

Most of those gains came in the outskirts of major cities, from Orange County to the suburbs of Dallas and Houston and on east to Philadelphia and New Jersey.

At the same time, Republicans strengthened their hold on more rural parts of the country, sweeping aside Democratic senators in North Dakota, Missouri and Indiana. With strong support from Florida’s more rural regions, Republicans may also have picked up the state’s Senate seat, which remains too close to call.

The results reinforced a pattern that emerged in Trump’s election, only now with even greater intensity, political experts said Wednesday.

“We have galaxies that are spinning away from each other,” said Paul Maslin, a longtime Democrat strategist who helped reelect Wisconsin Sen. Tammy Baldwin, among other candidates on Tuesday’s ballot.

“Suburban and metropolitan urban America is going in one direction, and rural, small town, ex-urban America is going the other direction,” he said.

Or as veteran political analyst Stu Rothenberg put it, “the reds are redder, the blues are bluer and the passion is more intense on both sides. The contrast couldn’t be sharper.”

Results from the 2018 midterm elections »

Republicans see that pattern playing to Trump’s advantage.

“Rural America has decided that Donald Trump is their guy,” said Scott Jennings, a Republican strategist and advisor to Senate Majority Leader Mitch McConnell (R-Ky.). “They see him fighting the media, they see him fighting the mob. He’s fighting battles on their behalf that no one else ever fought. That’s locked in and is never going to change.

“The coasts are still largely unhappy with him,” Jennings conceded. But so long as Trump can hold onto his base, he said, the president can stay within hailing distance of the electoral college majority needed for reelection. He can get the rest of the vote he needs if the economy remains healthy and if he’s willing to sometimes be “boring” and talk about it more, Jennings added.

“Donald Trump has a better than 50% chance of being reelected, and I didn’t see anything last night that changes my opinion about that,” Jennings said. “The urban-rural divide is what it was.”

Democrats see the matter differently. They note that their candidates, overall, won the congressional vote by about 7 percentage points. The swing from 2016, when Democrats lost the congressional vote by a point, represents one of the largest shifts since World War II, said Matt Grossmann, a Michigan State University political scientist.

If Democrats can maintain that edge, it would create a much more hostile environment nationally than Trump had in 2016, especially in the big industrial states of the Midwest and mid-Atlantic regions where Trump cemented his victory two years ago. Democrats made major gains in those states Tuesday night.

The biggest swings toward the Democrats came among women, especially college-educated whites, said Brian Schaffner of Tufts University, one of the directors of the Cooperative Congressional Election Study, a survey of 90,000 people that constitutes the largest academic study of U.S. voters.

Get the latest news from the nation’s capital on Essential Washington >> »

The survey showed that about two-thirds of college-educated white women voted for Democratic candidates, Schaffner said. That group, about 1 in 7 voters, was already among the Democrats’ biggest backers, but it moved an additional 8 percentage points to Democrats this year, the survey indicated. That was the largest swing of any major group, Schaffner said.

Voters younger than 40 showed a similar-sized shift toward the Democrats, Schaffner said. That included a significant number of those who had voted for Trump in 2016.

“Trump lost very few older voters” who sided with him in the last election, he said. But among younger voters, “he lost enough to make a difference.”

Two other surveys done for news organizations — the exit poll conducted for major television networks and a separate survey of more than 115,000 voters conducted for the Associated Press, painted a picture of the electorate that was largely the same as the academic survey.

The AP VoteCast survey showed that about 38% of voters cast ballots to express opposition to Trump, compared with about 26% who voted to express support.

The Democratic gains came mostly in suburban areas, especially outside the South, Schaffner said. In Southern suburbs, the two parties split the vote fairly evenly. Outside the South, however, Democrats won suburbs by 10 to 15 percentage points.

Midterm elections typically serve in part as a referendum on the party in power, but local and regional issues often play a role too. This time, the president overshadowed every other issue to an unprecedented degree, said Gary Jacobson, a political science professor at UC San Diego.

Trump in his news conference on Wednesday claimed credit for his party’s victories in the Senate and blamed Republican candidates who distanced themselves from him for their losses. The numbers rebut the second part of his claim, Jacobson said in an email.

“It was to the Republicans’ disadvantage that Trump was central to the electoral decision in House races, though it helped Republican Senate candidates in some of the red states,” he wrote.

Tuesday’s results will be eagerly analyzed by Democratic activists as they debate a presidential nomination fight that has already gotten underway and will now rapidly intensify.

The party’s left wing had high hopes for a trio of charismatic candidates who excited core Democratic voters, as well as House candidates in some swing districts who ran as unabashed progressives.

But none of the three progressive standard-bearers — Beto O’Rourke in Texas, Andrew Gillum in Florida and Stacey Abrams in Georgia — won their race. O’Rourke and Gillum have conceded defeat in their races for the Senate and governor, respectively. Abrams has not conceded, but trails significantly behind her Republican gubernatorial opponent, Brian Kemp.

“Democrats obviously broke through in the suburbs. Winning the House was significant,” said Maslin, the Democratic strategist. But “let’s not kid ourselves, those are states we wanted to win, and we didn’t.”

On the other hand, said political media strategist Don Sipple, “one has to be struck that they all ran as unapologetic progressives and all came very close.” And each of the three did at least as well as more moderate candidates have previously done in their states.

That “tells you something about the ‘new’ South,” said Sipple, who helped elect Govs. Arnold Schwarzenegger and Jerry Brown. It also keeps alive the argument that the best path forward for Democrats is to find candidates who can excite young voters and minorities, as opposed to those who hope to win back older, less liberal white voters who have moved to the Republican side of the aisle.

That’s a false choice, Maslin said. “Anyone who thinks it’s a zero-sum game, we can only do this, or a candidate should only do that, is wrong,” he said. “We have to do both.”

Lauter reported from Washington and Barabak from Los Angeles.

Lauter reported from Washington and Barabak from Los Angeles.

David.Lauter@latimes.com

Mark.Barabak@latimes.com

For more on Politics and Policy, follow me @DavidLauter