Democrats on Wednesday sought to capitalize on a decisive election victory in New York, with party leaders freshly emboldened to challenge Republicans on immigration and reinforce their focus on abortion and “MAGA extremism,” as they forge a blueprint to overcome President Biden’s low approval ratings this fall.

Democrat Tom Suozzi won a special election for Congress in suburban New York on Tuesday, where he campaigned as a practical problem solver who would work with Republicans and said his party hadn’t been tough enough on the southern border. His victory over GOP challenger Mazi Pilip flipped a seat once held by the disgraced George Santos and was the latest in a string of electoral wins for Democrats since they outperformed expectations in the 2022 midterms.

Party leaders received more good news in a special election for a vacant state House seat in suburban Philadelphia. Democrat Jim Prokopiak blew out his Republican opponent, Candace Cabanas, by 35 percentage points in an area where party turnout is seen as key to determining presidential outcomes in battleground Pennsylvania.

The results provided some relief for Democrats reeling from a difficult stretch that included a new round of public polls showing that voters have acute concerns about Biden’s age and the job he is doing, as well as a special counsel report that offered an unflattering view of the president’s mental acuity. Many in the party cheered the results Tuesday — Suozzi was ahead of Pilip by about eight points, with some votes still being tallied — and pointed to them as a road map for navigating a challenging electoral landscape.

“One key takeaway that Suozzi demonstrated is that you don’t run away from a contentious issue. You lean into it, and then you double down and triple down on it. And that’s exactly what he did on the issue of border security. He refused to allow the Republicans to define him on the issue,” said Steve Israel, a former congressman from New York who used to head the House Democratic campaign arm. “The fundamental lesson of the special election: Suozzi showed Democrats how you can meet voters where they are.”

But the run-up to November, when Biden and former president Donald Trump are on course for a rematch and the balance of power in Congress is up for grabs, is strewn with obstacles for the party, some strategists and nonpartisan analysts said. Suozzi’s win doesn’t eliminate long-term concerns about Biden’s age. And a key part of Suozzi’s strategy involved distancing himself from the president and the national Democratic brand.

“I do think it shows that suburban voters value competence, and Suozzi was the candidate they knew better and trusted to come up with solutions even as Biden’s approval ratings are upside down virtually everywhere on the migrant crisis,” said David Wasserman of the nonpartisan Cook Political Report. “The challenge for Biden is that voters don’t see him as competent.”

Republicans publicly downplayed the significance of the special election result, even as some in the GOP worried that Trump and the farthest-right figures in their party hurt them in the suburbs. They said the overall dynamics will become more favorable to them in the general election, with Trump turning out the party’s less-engaged voters and Biden playing a larger role in the public conversation.

GOP leaders argued that Suozzi, who previously held the seat for three terms, was a uniquely strong candidate against Pilip, relatively a political newcomer. They predicted Democrats would fare worse in competitive races once Biden is at the top of the ticket.

House Speaker Mike Johnson (R-La.) dismissed Suozzi’s win, saying he overcame the immigration issue by campaigning “like a Republican.” “That is in no way a bellwether of what’s going to happen this fall,” he told reporters. (Johnson had said in a Jan. 18 fundraising email that the “future of our Republican Majority could rest on this race’s outcome.”)

But Democrats rallied around Suozzi’s model, especially his posture on immigration, which polls show is one of Democrats’ toughest issues. Republicans believed border security would be their winning issue at a time when New York is facing a massive influx of migrants. They had pointed to January polling showing that voters trusted Trump over Biden on the issue by more than 30 points.

With immigration at the forefront of New York voters’ minds, Suozzi called for stronger security at the border but also maintained support for a path to citizenship for undocumented immigrants. He also pointed to House Republicans’ refusal to take up a bipartisan border security bill, arguing that GOP lawmakers weren’t serious about finding a solution.

Sen. Chris Murphy (D-Conn.) sent a memo to his Senate Democratic colleagues calling Suozzi’s win a “road map for Democrats” because he “turned what could have been a devastating political liability into an advantage.” Other Democrats voiced a similar sentiment.

Jon Reinish, a New York Democratic strategist, said that the party has long tried to ignore contentious issues such as immigration and crime and that he hoped Suozzi’s embrace could “break this sort of stale stalemate thinking in Washington that has in many ways paralyzed the party and denied them a lot of wins, and a lot of public approval.

“And I hope the Biden campaign sees that too,” he said.

Biden has led a shift in the party toward a more combative approach against Republicans on immigration, blaming Trump and his allies for sinking the border security package on Capitol Hill. White House spokesman Andrew Bates renewed that criticism Wednesday, saying in a statement that the New York election was a “devastating repudiation of congressional Republicans.”

Biden’s campaign noted that Republicans put millions behind commercials mentioning Biden in the New York special election — and lost. Biden congratulated Suozzi even though the Democrat publicly questioned whether the president will be the nominee during an interview on “Good Day New York” the day before the election.

Suozzi’s record on immigration put him in a strong position to hit back on that issue and dispute Republicans’ portrayal of him as an “open-border radical.” GOP ads played nonstop a clip of the Democratic candidate saying he “kicked ICE out of Nassau County,” but Suozzi hit back with his own ads showcasing footage of him defending ICE on Fox News — introduced by a host as “one of the few Democrats who voted to support this vital agency.”

Republicans said Wednesday that many others in Suozzi’s party will not have the same advantage, particularly as they face pressure from some on the left to adopt a more welcoming stance toward undocumented immigrants.

“How many Democrats have the will, capacity and body of work to effectively paint themselves as Republican on immigration?” asked Dan Conston, the president of the Congressional Leadership Fund, the biggest independent advertiser for Republican House campaigns. “This is clearly a potent issue.”

Early Republican polling found that the initial immigration attacks on Suozzi had caused severe damage to his support in the district, forcing millions in Democratic defensive spending.

Suozzi’s campaign spent more than $4 million on ads, compared with $361,114 for Pilip, who also joined forces with the National Republican Congressional Committee to buy additional ads, according to AdImpact.

Pilip, a little-known county legislator, was much more guarded than Suozzi on the trail and a notably less confident public speaker. Criticizing Democrats’ border policies at one of her relatively few news conferences, Pilip spoke for just a few minutes and looked down at her notes. She also struggled to raise money, a perennial issue for Republican House candidates.

Trump lambasted her on social media late Tuesday after her loss, calling her a “very foolish woman” who didn’t endorse him. Pilip had tiptoed around Trump, declining to say whether she voted for him in 2020 until later acknowledging that she had — playing into Democrats’ argument that she was an unknown quantity in a district burned by Santos, a Republican.

Democrats hammered Pilip on abortion — suggesting she was beholden to an antiabortion party, even as she said she opposed a national ban — and tied her to the MAGA brand, which many Republicans believe has cost them in the suburbs. In Pennsylvania, Prokopiak used similar attacks against his Republican opponent, labeling her a “MAGA extremist,” referring to an acronym for Trump’s “Make America Great Again” campaign slogan.

Attacks on Republican-led restrictions on abortion rights and threats to democracy have helped lead Democrats to victories in elections, including the Kentucky governor’s race last fall. Democratic-aligned activists also have had success focusing attention on abortion, waging successful campaigns on ballot initiatives in conservative states such as Kansas and Ohio.

Republicans acknowledge that they have a problem turning out their voters in special elections but suggested that the disadvantage would dissipate in the November general election. Republican strategist John Feehery, a former top staffer for GOP leaders in the House, said Tuesday’s outcome underscored Republicans’ need to improve their turnout in lower-profile elections as well as to recruit stronger candidates, not just banking on moving personal stories.

“What the Republicans have to understand is they are not the high-propensity party anymore,” he said.

Azi Paybarah and Marianna Sotomayor contributed to this report.