Washington (CNN) Democrats flipped their 41st state legislative seat of Donald Trump's presidency, winning a special election Tuesday night in the Philadelphia suburbs.

Democrat Helen Tai bested Republican Wendi Thomas in the Bucks County race -- notching a 96-vote victory in a district that has previously favored Republicans, with Trump winning there by 3 percentage points in 2016 and Mitt Romney by 13 points in 2012.

It's the latest evidence of America's suburbs shifting in Democrats' favor since Trump took office.

Former Vice President Joe Biden endorsed Tai in the race, and the Democratic Legislative Campaign Committee said Tai's campaign knocked on 40,000 doors in the district.

The wins in state legislative races are seen -- in part because the candidates are typically little-known -- as gauges of voters' enthusiasm in small slices of the country. Other races, including a state supreme court contest in Wisconsin, have also shown major movement in Democrats' favor in key states since Trump took office.

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