SOUTH ST. PAUL — Democrats have endorsed former state Rep. Mike Obermueller in his second attempt to unseat Republican U.S. Rep. John Kline in Minnesota’s 2nd Congressional District.

Obermueller won the Democratic-Farmer-Labor endorsement on the first ballot in a three-way contest Saturday at the party’s convention at South St. Paul High School. The other candidates, political newcomers Thomas Craft and Paula Overby, both of Eagan, conceded before the vote was announced.

Craft and Overby have both pledged not to challenge the endorsed candidate in the Aug. 12 DFL primary.

Obermueller told the delegates he’ll be a stronger candidate this time around. The Eagan attorney cut Kline’s margin to 54 percent to 46 percent in 2012, down from the incumbent’s 26-point spread over a DFL challenger in 2010.