At the Bucks County Democrats’ first meeting since the April 26 Pennsylvania primary, one worry dominated: Donald Trump had done better than expected in this blue-leaning exurban expanse north and east of Philadelphia.

At one polling place, these Democrats’ Republican neighbors — nice people, nothing like the Trump supporters they had seen throw punches at protesters — were proud enough to grab lawn signs.

“It was stunning,” said Stan Durey, 67, a former security analyst who works at a car dealership. “I just stood there shaking my head, going, ‘Really?’ It wasn’t two, it wasn’t three — it must have been 20 or 30 people walking away with Trump signs. To me, that’s an alarm bell.”

Across the country, Trump has performed best in the sorts of places Democrats could afford to lose: landslides in Appalachia or in white counties of the Deep South. To win the White House in November, he must extend his appeal to unlikely states and unlikely parts of those states. In one of those places — the suburbs of Pennsylvania — Trump is not as toxic as Democrats expected.

Democrats’ 2016 victory plan resembles the one President Obama deployed in 2012: outrunning Republican gains with conservative whites by turning out nonwhite voters and voters in the suburbs — especially women in the suburbs.

Leslie Rossi painted her property red, white, and blue to drum up support for Donald Trump ahead of the state’s Republican primary on Tuesday. Rossi believes this final push to promote pro-Trump delegates is critical to ensuring a Trump nomination. (Dalton Bennett/The Washington Post)

Obama won just 13 of 67 Pennsylvania counties four years ago, but his margins in Philadelphia and its suburban sprawl, including Bucks, Delaware and Montgomery counties, overwhelmed the Republican vote in its rural strongholds. Since 1988, the last time a Republican presidential candidate won the state, all three suburban counties have flipped from majority Republican registration to majority Democrat.

The question is whether the modern math still holds. Democrats see opportunities with nonwhite voters alienated by Trump, and they are encouraged by polls that show Arizona, Georgia and North Carolina as battlegrounds. But the flip side is Trump’s potential to win industrial states such as Pennsylvania and moderate suburbs such as Bucks County that were seen as safe or trending blue.

The math would seem to work against him. Obama won Pennsylvania by around 310,000 votes; he won Philadelphia and its collar counties with a margin of 615,895 votes. In 1988, Michael Dukakis netted just 28,450 votes from the region. What had been a swing vote had become a firewall.

That has not stopped suburban Democrats from marveling — and agitating — about Trump’s unexpected popularity in their communities.

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Searching for an explanation

At the party meeting in Doylestown, Jean Mollock, 61, passed the plate of mozzarella and tomatoes that was going around the table and asked, “Why don’t we try to understand why Trump is so popular?”

Others said that there was nothing to understand. “You think there’s some logic behind it?” asked Durey. “I’m saying there’s not.”

Neil Jesiolowski (in green shirt), chairman of the Nockamixon Democratic committee, speaks during a post-primary meeting at Capri Pizza in Bucks County, Pa. (David Weigel/The Washington Post)

Mollock shook her head. “I don’t think life is logical,” she said. “I’m not looking for logic — I’m looking for understanding. Crazy understanding, if that’s what it is.”

Causing additional worry for Democrats is that Republicans here have largely embraced Trump faster than expected. They have adopted his nothing-to-see-here spin to explain his gaffes and scandals. In particular, they view his apparent lack of interest in social issues as an opening in the suburbs, where — since the 1990s — once-dominant Republicans often lose moderate voters.

A May 10 poll by Quinnipiac University rattled some Democrats here, showing a one-point lead for Clinton — and voters trusting Trump more to handle terrorism and the economy.

“I’d have been very confident if they’d nominated Sen. [Ted] Cruz because he would have done terribly in the Philadelphia suburbs,” said U.S. Rep. Brendan Boyle (D-Pa.), whose district covers safely Democratic parts of Philadelphia and Montgomery County. “The question with Trump is, will he be able to get votes that your typical Republican, like Mitt Romney, couldn’t get? It’s a real X-factor.”

Just a few months ago, Democrats thought they understood the Trump factor. He was divisive and unpopular, the one Republican hopeful whom senators and other office-holders seemed terrified to contemplate. In polls, he lost to Democratic front-runner Hillary Clinton; he did not pose a threat to the party’s demographic future like Sen. Marco Rubio (R-Fla.) seemed to.

The Trump who made it out of the primaries seemed to gain strength, especially from the contrast with Cruz. Over three months of contests, Trump won 42 percent of the vote from moderate and liberal GOP primary voters. Trump’s lead over Cruz was largest among moderate and liberal Republicans, and his favorable numbers inside the party increased as he won primaries in New York and Pennsylvania.

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“I’ve never seen this much excitement in Pennsylvania in my life,” said Rep. Lou Barletta (R-Pa.), who represents part of the moderate Lehigh Valley and rose to prominence as a mayor cracking down on illegal immigration. “I can’t tell you how many people come up to me, say they haven’t voted in 20 or 30 years, and say they’re for Trump. Strong, Democrat[ic] areas, union members — they’re voting for Trump.”

Trump won more than 70 percent of the vote in parts of Barletta’s district.

Political analysts here surmised that most of the 60,000 voters who switched from the Democratic Party to the GOP before the primary intended to back Trump.

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But conservative Democrats in western and central Pennsylvania had been making that switch for more than a decade. What surprised Republicans was Trump’s dominance in the Philadelphia suburbs, along the old “Main Line” of wealthy towns and the increasingly liberal Bucks County. Trump won Montgomery County by 19 points over Ohio Gov. John Kasich and won outright majorities in Bucks County, Delaware and Philadelphia.

Despite such data points, some Democrats remain bullish that the hill is too steep for Trump to climb.

“Will he have some appeal to working-class Dems in Levittown or Bristol? Sure,” said Ed Rendell, the former Pennsylvania governor and Philadelphia mayor, who won landslides in the suburbs. “For every one he’ll lose one and a half, two Republican women. Trump’s comments like, ‘You can’t be a 10 if you’re flat-chested,’ that’ll come back to haunt him. There are probably more ugly women in America than attractive women. People take that stuff personally.”

Anger provides an opening

In conversation, Republican voters here fit into three camps: Those who embraced Trump, those who rationalized him and a very small minority that rejected him. (The last group was the least inclined to reveal their names.)

On Saturday, after a meeting of a Republican club in Bucks County’s New Britain, one activist grumbled that he might “stay home and throw up” on Election Day. The rest were optimistic about Trump.

“There’s been a tremendous increase in Republican votes,” said Nina Bolfing, 65. “We had 950 people in our area — that was more than twice what we saw last time. I have reservations about Trump, but I have to take this chance.”

In Montgomery County, at a Ukrainian soccer club that hosted a fundraiser with local Republican candidates, there was the same preponderance of good feeling. Brian Fitzpatrick, the brother of Bucks County’s retiring congressman Mike Fitzpatrick, joined a Beatles cover band singing “With a Little Help From My Friends.”

“They always talk about Hillary having experience, but not all experience is good experience,” said Gary Tiller, 65. “I think Trump can do something to cross party lines. I don’t like the way he talks sometimes, but the way people talk in politics hasn’t been working.”

Tiller’s wife, Maggie, 64, was even more ready to defend Trump’s statements. “There’s a lot of truth in what he says,” she said. “He used his own money to run. He didn’t have a super PAC or anything — when you do, you’ve got to do what they say.”

Joe Cunningham, a 60-year old activist from Montgomery County, was forgiving of Trump. “There’s not gonna be a wall,” he said, casting doubt on the candidate’s most famous pledge, to force Mexico to pay for a wall across the southern border. “Environmentally, you can’t do it.”

When the primary came, Cunningham looked at his options and backed Trump. “When Kasich and the other guy made that deal, I was like, ‘Screw you guys,’ ” he said. “To me, the more the establishment says, ‘We don’t want him,’ the more I want him.”

The burning, seemingly unstoppable anger at the “establishment,” however defined, has given Trump an opening that Clinton cannot exploit. The Doylestown Democrats wrestled with Clinton’s image as they contemplated why, exactly, Trump was so popular. Samuel Kolodny, 49, suggested that Sen. Bernie Sanders of Vermont might be more electable than Clinton; he was reminded that Clinton was sewing up the nomination.

“I worked in construction for 35 years,” member Joe Frederick, 65, said. “These guys say, ‘Look, Republicans haven’t done anything for us.’ They’re not the educated people that went to college; they’re seeing that the jobs are taken by minorities, because it’s cheaper to hire them. You got the Russians, you got the ethnic groups that are in there doing siding. I see it every day in construction. That’s why there’s anger.”

Trump seemed to be winning over even the people whose jobs were safe, or who were happily retired and enjoying their pensions. His image was supposed to be toxic in this part of the country; so far, it is not.

Changing that would take a concerted campaign, John Dougherty said. He has led the local branch of the International Brotherhood of Electrical Workers since Bill Clinton was president.

“There’s still a little frustration, a little racism in this world,” Dougherty said. “The novelty of Donald Trump will wear off, okay?”

It would not wear off on its own. People who had never contemplated voting Republican for president were considering Trump, Dougherty said. He would do anything he could to stop that, and he had an idea. To expose what he said is a gap between Trump’s promises and his potential, he would print at least 10,000 baseball caps, designed to look like the candidate’s “Make America Great Again” caps.

“Mine are gonna ask how he does all this,” said Dougherty. “H-o-w, with an exclamation point. I’m dead serious.”