For most of the last half-century, the state House seat in the 161st District in Delaware County has been held by Republicans - 38 of the last 46 years.

That seat is just a small part of a deep political history in Delaware County, where the landscape has long favored Republicans, where victories for Democrats have been long shots - and where, as a result, turnout among Democratic voters has been haphazard at best.

But on Tuesday, Democrat Leanne Krueger-Braneky captured the seat in a special election, turning the 161st blue for the first time in five years.

While results remain unofficial - absentee ballots and write-in votes are still being tallied - Krueger-Braneky managed a win with at least 48 percent of the vote, more than endorsed Republican candidate Paul Mullen, who received 42 percent.

About 10 percent of votes cast were write-ins, the majority of which likely went to Republican Lisa Esler, who mounted a campaign against Mullen after she was passed over for the party nomination.

Krueger-Braneky's win is likely to stand at a margin of fewer than 1,000 votes once all ballots are tallied. Yet her party's leaders have heralded the victory as an important signal for Democrats across the county - an indication that voters are "tired of the Republican machine."

Republican leaders, meanwhile, have chalked the loss up to what happens when a "party isn't unified."

The win is likely to have effects at the county and state levels. For the first time in years, the number of Democratic state representatives from Delaware County matches the number of Republicans at five each.

And after capturing a win in a district led by Republican voters, Krueger-Braneky's victory indicates that enough voter turnout can overcome party advantage, said David Landau, chairman of the Delaware County Democratic Party.

"I think voters are sending the message that they are tired of a stalemate," said Landau.

In the last two years, Democrats have increasingly seen signs that they are growing in favor in the county. Gov. Wolf won Delaware County handily in November 2014. President Obama did the same in 2012. And in 2013, for the first time in decades, registered Democratic voters outnumbered registered Republicans. Now, there is Krueger-Braneky.

"Democrats from all over the county recognized the importance of this race," said Landau. "It shows the extraordinary ground game we can put together."

Voter turnout was slated to be particularly challenging for the midsummer special election, a time when many voters are on vacation and the polls are far from their minds. Still, nearly 24 percent of the district's 45,000 voters cast ballots; 735 of the votes were absentee.

"It was disappointing, but not unexpected," said Andy Reilly, chairman of the Delaware County Republican Party. "Any time you have two Republicans, you are going to give advantage to the Democrats."

The county Republican Party faced criticism from inside and outside in this election over its selection of Mullen, who supported some policies that strayed from party lines. Esler used Mullen's position on issues such as liquor privatization and education funding as political capital, siphoning votes away from the endorsed candidate.

Krueger-Braneky said she would be sworn into office Aug. 25 and would immediately begin working alongside fellow Democrats to negotiate the state budget, which is more than a month late. The Swarthmore businesswoman, 38, said Wednesday that her priorities will be a better funding formula for public education and closing loopholes that allow large corporations to receive tax incentives.

"Voters wanted a change," Krueger-Braneky said. "We saw that last night."

"But this wasn't just about the 161st," she added. "This is about continuing to build Democratic power in Delaware County."

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