The 2020 election established Montgomery County as a powerful Democratic stronghold in Pennsylvania

As holiday decorations went up across Montgomery County this month, the reindeer and the Santas shared lawn space with Biden-Harris signs.

“They’re still up and I think it’s intentional,” said Jane Murray, a Democratic committeewoman who lives in Ardmore. A rebuttal, perhaps, to President Donald Trump’s refusal to concede his election loss. Or maybe, she thought, a lingering celebration of the overwhelming Democratic turnout in these suburban towns west of Philadelphia, which helped deliver Pennsylvania to Joe Biden and make him president-elect.

While Philadelphia and Pittsburgh have traditionally driven the Democratic vote in Pennsylvania, the suburbs showed up huge for Biden. And the biggest and bluest of them all is Montgomery County, whose leftward swing, while expected, still managed to defy expectations. Biden won the county with a margin 50% larger than Hillary Clinton’s in 2016 and double President Barack Obama’s in 2012.

“The numbers were just remarkable,” said Rep. Madeleine Dean, a Jenkintown Democrat. “I said Montgomery County will be the linchpin for the state, and that came absolutely true. ... I predict that we will continue to be sort of one of the most important counties in the country.”

The strong Democratic showing elevates the already substantial political relevance of the county, home to party leaders like Attorney General Josh Shapiro, who lives in Abington and is widely expected to run for governor in 2022. And it raises the prospect that Montgomery County is becoming another Philadelphia on the state’s political map — a place where Democrats can expect smashing margins in statewide races to offset the party’s struggles with white working-class voters elsewhere.

“I don’t see how you win Pennsylvania without Montgomery County,” said County Commissioner Val Arkoosh, who is herself considering a run for U.S. Senate in 2022. “Montgomery County kind of represents many different aspects of Pennsylvania, just within one county, so if you’re successful here, I think it [positions] you well to be able to be successful across the state.”

Home to Valley Forge and high school home court to the late Kobe Bryant, Montgomery is a diverse county, with affluent towns like Gladwyne, more urban areas like Norristown, and rural, Republican pockets in the northern tip.

Biden’s victory here was huge.

He won 319,000 votes in Montgomery County, the third-most of any county and a 63,000-vote increase over Clinton’s 2016 vote total there (Clinton lost the state by about 44,000 votes, while Biden won it by 81,000). Nearly every municipality shifted Democratic compared with 2016. It had the largest shift leftward of all the Philadelphia collar counties.

Voter turnout was 82%, compared with 71% statewide.

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For longtime observers of county politics, the leftward swing, while it’s been building for years, is nevertheless stark. In the 1990s, Montgomery County was a Republican stronghold. Former Democratic Rep. Joe Hoeffel represented it in Congress, but Republicans controlled the county and most municipal governments.

“When I was growing up, if you weren’t a Republican, you didn’t get your trash picked up,” said Nancy Guenst, the outgoing Democratic mayor of her native Hatboro.

Her mother worked as secretary for the county GOP. Guenst first registered to vote as a Republican.

Now she’s headed to Harrisburg. She’ll be the first Democrat to represent the 152nd District in the state House, after winning an open seat vacated by longtime Republican Rep. Tom Murt.

Murt, a moderate Republican, said that to win as a GOP candidate in a majority-Democratic district, he concentrated on constituent services and bipartisan policies like disability-rights legislation. In his last few elections, his Democratic challengers had come closer and closer to beating him. Guenst defeated the Republican nominee, Karen Houck, by 9 percentage points.

“If the Republican Party wants to be a player here, they’re going to have to find some Republicans who are willing to work with Democrats,” Murt said. “... Who are willing to respectfully reach across the aisle.”

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The overwhelming majority of Montgomery County is now represented by Democrats in Harrisburg, and most municipalities and school boards are controlled by Democrats. Last year, three Democratic women replaced three Republican men on Upper Gwynedd’s town commission, making it Democratic-controlled for the first time — and entirely run by women.

State Rep. Tim Briggs, who has represented Montgomery County since 2009, said the election results solidify the county’s importance in statewide elections. The county’s population has grown about 4% since 2010, with families drawn to good schools, leafy suburbs, and proximity to the city.

“We are a growing county and that definitely changes the worldview here,” Briggs said. “A lot of younger people moving in starting families are less entrenched in the way of old thinking.”

Many older or more moderate voters have also shifted in their political leanings, a trend long underway across the region but accelerated in the aftermath of Trump’s election. The county’s Republican voter registrations dropped by about 8,000 in the last four years, while Democrats gained 34,000.

“Folks who were sort of more middle-of-the-road Republicans have changed their registration or are simply voting for Democratic candidates,” said Neil Deegan, a Democratic strategist who lives in Glenside.

But even in Montgomery County, Democrats couldn’t avoid some of the crushing down-ballot losses that cost the party its chance to take over the state House. Republican State Rep. Todd Stephens hung on to his seat. While Trump lost Montgomery County by 26 percentage points, Stephens nearly tripled his margin of victory from 2018.

And state Treasurer Joe Torsella, a Flourtown Democrat who was seen as a possible candidate for governor or Senate, received about 22,000 fewer votes than Biden in the county on his way to a surprising loss.

“I think the election we just had has a lot of messages for the party that we need to be aware of if we want to stay on top of our game,” said Joe Foster, who chairs the Montgomery County Democrats.

That will involve figuring out how to bring in more moderate voters who rejected Trump but voted for other Republicans, while also engaging the more progressive wing of the party, which “absolutely exists in the suburbs,” Foster said.

“We’re a lot more progressive than people sort of think about when they go, ‘Oh, the suburbs,’” said Rachael Chou, a 40-year-old mother of two in Bryn Mawr. “People might be thinking about my mom, who actually is progressive, but it’s actually me living here now and I’m even more progressive.”

Chou, a party committeeperson in Lower Merion, which saw the biggest Democratic shift in the Philadelphia suburbs, has made a point of recruiting within her network of new moms in the area.

“The parents around here are attorneys, heads of marketing,” she said. “In the past we made a little mistake of not reaching out to those people, or maybe we didn’t know how to reach them.”

Murray, the committeeperson from Ardmore, said the momentum can stick because it started long before 2020.

“People have started becoming more involved as sort of a habit rather than a reaction,” she said.

And local issues are driving engagement. In her community, those include gentrification and social justice movements. Trump had no chance of minimizing his losses in the suburbs, Murray said, because his pitch to “suburban housewives” showed that he fundamentally misunderstood what they looked like.

“The president’s comments about the suburbs fell on deaf ears. ... It just seemed like such a joke of a comment,” Murray said. “I mean, look around.”