In 2012, Democrat Mike Obermueller came across as an affable, promising candidate in need of experience and polish when he sought but failed to win the Star Tribune Editorial Board's endorsement in Minnesota's Second Congressional District. Two years later, Obermueller, a one-term state legislator out of office since 2010, is still a promising candidate in need of experience and polish. While he's been a more able attack dog in this rerun race against Republican U.S. Rep. John Kline, Obermueller still quickly seems out of his depth on key topics — health care, the economy, foreign policy — once the usual Democratic talking points have been recited.

In contrast, Kline, who's running for his seventh term, has deep expertise in labor, pension and education issues, thanks to his powerful post as chair of the House Committee on Education and the Workforce. He's also capable of putting on impromptu foreign policy seminars when he sits down with the Editorial Board, using knowledge complemented by his 25 years in the Marine Corps and his travels to war zones while in office.

It's that expertise, and a strong record of getting serious legislation enacted, that has earned Kline a return trip to Congress despite a reputation that has been tarnished by his coziness with for-profit colleges. While Obermueller, 41, has made justifiable political hay out of that issue, the Democrat has not made a compelling argument for why he's ready to ready to replace Kline. Nor has Bill Maher, the comedian who spotlighted this race in his HBO show's "Flip A District" contest.

Kline has struck an impressive balance between enacting major legislation (workforce training, steadying student loan interest rates) while still tending the home fires. An example: Kline was a strong advocate for building a new overpass for a dangerous Hwy. 52 intersection in Goodhue County.

Kline's work on legislation to protect child sex trafficking victims is also commendable, as is the legislative fix he championed to help members of the Minnesota National Guard and other soldiers get overdue bonus pay. In addition, Kline has cast sensible votes to raise the debt ceiling and resolve early 2013's "fiscal cliff." He was not among his party's radicals.

Paula Overby, the Independence Party candidate, deserves a shout-out for her boxing-themed campaign ad. But Overby, believed to be the state's first transgender congressional candidate, seemed to have only a thin knowledge of key issues, such as health care.

Voters would be shortsighted to dismiss a candidate with Kline's clout. The silver-haired representative deserves their support, with the caveat that he needs to more aggressively hold disreputable for-profit colleges accountable.