Updated: 10:31 p.m.

Democratic Rep. Rick Larsen won re-election in Washington state, defeating Republican challenger John Koster with 51 percent of the vote, the Associated Press reported Monday night.

Because the 2nd district votes completely by mail and envelopes needed only to be postmarked by Nov. 2, the vote count continued well past Election Day.

Larsen thanked voters and his campaign staff and volunteers following the release of the new tally. “The days since the election have been an exciting time for our local democratic process,” he said in a statement. “This election proves that every vote counts. And I want to thank every person who took the time to participate and cast a ballot in this race.”

Seven House contests from last week remain undecided. They are in California’s 11th and 20th districts, Kentucky’s 6th district, Illinois’ 8th district, New York’s 1st and 25th districts, and Texas’ 27th district. All of the races involve Democratic incumbents.

Republicans lead in five of the races: Democratic Reps. Jim Costa (Calif.), Melissa Bean (Ill.), Tim Bishop (N.Y.), Dan Maffei (N.Y.) and Solomon Ortiz (Texas) trail their opponents.

Meanwhile, Democratic Reps. Jerry McNerney (Calif.) and Ben Chandler (Ky.) have the lead in their too-close-to-call races. Several of the contests, such as the ones involving Ortiz, Bishop and McNerney, are expected to go to recounts.