The five Minnesota Democrats in the U.S. House, including freshmen Tim Walz of Mankato and Keith Ellison of Minneapolis, decisively swept their races Tuesday,

The others who won reelection were Fourth District Rep. Betty McCollum, Seventh District Rep. Collin Peterson and Eighth District Rep. Jim Oberstar.

Republican Erik Paulsen, a seven-term member of the Minnesota House, defeated Democratic political newcomer Ashwin Madia late Tuesday in the closely watched and hotly contested battle to replace retiring U.S. Rep. Jim Ramstad in the western Twin Cities' suburban Third Congressional District. Republican John Kline was re-elected in the Second, defeating Steve Sarvi.

Walz and his Republican opponent, Mayo Clinic physician Brian Davis of Rochester, waged the most intense race among the five. They sparred from the start, each claiming that the other too eagerly toed their party lines to represent the largely rural First District in southern Minnesota.

Davis said that by 9:30 p.m. Tuesday it was clear that Walz was headed toward victory. He called Walz about 10:25 p.m. and conceded.

"I wanted to congratulate him on his substantial victory," Davis said. "We had an uphill battle, and we made substantial progress, but we didn't get there. Of course there's some disappointment that we were not successful, but the sun will rise tomorrow."

Davis said the time and energy he spent earning the GOP endorsement and battling state Sen. Dick Day of Owatonna in September's primary were partly responsible for his loss because it took away from preparation for the general election.

Earlier Tuesday evening, Walz had said: "Over the past few days, I've traveled to every corner of the district talking to ordinary, middle-class citizens. They know that we can come together, not as Democrats or Republicans, but as Americans, to get the economy back on track, make us energy independent and make health care more affordable."

Energy was an issue where differences were evident in the race. Walz voted for a House bill that included offshore oil drilling, but he is a strong advocate for alternative fuel sources. Davis touched upon the latter, but pushed for drilling in Alaska's Arctic National Wildlife Refuge. The two butted heads about how to save Social Security, but had common ground on the financial rescue bill that Congress approved; Walz voted against it, and Davis said he would have done so as well.

Independence Party candidate Gregory Mikkelson, a farmer from Lake Crystal, also vied for the First District seat.

In the Fifth District, Ellison was challenged by Republican Barb Davis White and Independence Party candidate Bill McGaughey. En route to victory two years ago, Ellison overcame endorsement and primary challenges within the DFL. This time around, the state's first black congressman and Congress' first Muslim, had it easier, facing two lesser-known challengers who lagged in funding.

In accepting his victory, Ellison told supporters to go have fun "because tomorrow, the hard work starts."

Ellison also noted Barack Obama's victory. "A hundred years from now, we'll look back at this as a watershed moment in American history," he said.

Davis White, a minister, advocated eliminating health maintenance organizations and building 600 nuclear power plants.

McCollum, a four-term incumbent, faced Republican attorney Ed Matthews. McCollum's focus was health care, education and human rights.

Matthews opposed earmarks and favored making President Bush's 2003 tax cuts permanent.

Peterson, seeking a 10th term, was challenged by Republican Glen Menze, an accountant and farmer who lost to him in 2000. Peterson, chairman of the House Agriculture Committee, led passage of the federal farm bill this year.

Menze, who describes himself as a "populist conservative," advocated permanent tax cuts and less government interference in small businesses.

Oberstar ran for his 18th term against GOP newcomer Michael Cummins. Oberstar serves as chairman of the House Transportation and Infrastructure Committee, where he helped secure funds for rebuilding the Interstate 35W bridge.

Cummins is a real estate developer and construction manager. Among his positions, he advocated eliminating automatic citizenship for children born in the United States to illegal immigrant parents.

Chao Xiong • 612-673-4391