Alex Wong/Getty Images Democratic U.S. House candidate and Virginia State Sen. Jennifer Wexton.

Democratic candidate Jennifer Wexton has unseated Republican incumbent Rep. Barbara Comstock in Virginia’s 10th district.

The seat had been held by Republicans for decades, but GOP support in the Washington, DC, suburbs has waned with each election.

Jennifer Wexton, the Democratic state senator challenging Republican incumbent Rep. Barbara Comstock in Virginia’s 10th congressional district, has won the highly competitive seat in the suburbs of Washington.

NBC News and others projected that Wexton had won shortly after polls closed on Tuesday, signalling a likelihood that the final tally will be a large gap.

Read more: Opposition to Trump is making the DC suburbs finally turn blue

Comstock had weathered tough races before, including a sizable victory in 2016 when the district also went for Democratic presidential nominee Hillary Clinton. But the backlash against President Donald Trump and his agenda in Washington’s backyard had proved to difficult to navigate.

Wexton had garnered support from the large contingency of federal government employees, many of whom hold a negative view of Trump.

Wexton had also converted former FBI Director James Comey, who until 2018 had only donated to Republicans. Comey donated the maximum legal amount to Wexton and even canvassed for her campaign in the final days of the election.

Wexton credited her surge in support with the heavy opposition to Trump from the district, which resulted in what she viewed as increased enthusiasm for her campaign.

“One of the things that is also helping is that in the post-Trump era, I think a lot of people realised just how fragile our democracy is and they realise that it’s important that they get out and vote and make their voices known,” she told Business Insider in an October interview. “People recognise that they can’t just sit on the sidelines and assume everything’s going to be OK.”

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