Matt Varilek, a former aide to Sen. Tim Johnson, D-S.D., has won the Democratic House primary in the state's lone congressional district, beating back a challenge from a county commissioner.
The Associated Press called the race for Varilek just before 10 p.m. Eastern time. With 64 percent of precincts reporting, Varilek led Jeff Barth 73 percent to 27 percent.
Barth took a huge lead in media attention in the final weeks of the primary, thanks to a quirky, meandering, biographical Web ad that went viral. But Varilek outspent him by a healthy margin and was widely considered a more electable candidate in the general election. He advances to a tough general election matchup against GOP freshman Rep. Kristi Noem, a rising star in the House Republican conference.