Democratic Rep. Sean Casten won reelection to a U.S. House seat representing Illinois on Tuesday. Casten, a scientist and businessman-turned-politician, has focused on the environment and fighting climate change. He first won office in 2018 when he flipped a longtime Republican territory in Chicago’s suburbs and ousted a six-term incumbent. The redrawn district leans Democrat and is largely comprised of communities southwest of the city, along with a handful of neighborhoods on Chicago’s South Side. The Associated Press declared Casten the winner at 10:59 p.m. EST.