Democrat Derek Tran has defeated Republican incumbent Michelle Steel for a House seat representing California’s Orange County and Los Angeles, NBC News projects, after a contentious race that centered on the candidates’ Asian American identities and use of aggressive anti-China messaging.

Derek Tran, a first-time Democratic candidate, has flipped a toss-up California House seat, narrowly defeating GOP Rep. Michelle Steel, who conceded on Wednesday after a protracted vote count. Tran had declared victory early this week, and currently leads by roughly 600 votes.

Democrats have taken control of California's 45th Congressional District from the GOP, with Republican Rep. Michelle Steel losing her Orange County House seat to Democrat Derek Tran, CBS News projects.