The district has not been good to Democrats in the past. Mitt Romney won the district in 2012 even though he lost the presidential race in Wisconsin and nationally to Barack Obama. Trump crushed Hillary Clinton in the district in the 2016 presidential election and John McCain almost won the district in 2008, despite Obama’s easy statewide victory.

Democrats saw Tuesday’s victory as a sign they were taking hold of the energy that benefited their party in special elections last year in Alabama, Virginia and Oklahoma.