Since his surprise victory over DFL stalwart Jim Oberstar two years ago, U.S. Rep. Chip Cravaack has been in the cross-hairs of Democrats from Duluth to Washington.

Early Wednesday morning, that effort succeeded and the freshman Republican, trailing by 6 percentage points, conceded to DFL challenger Rick Nolan, who had returned to politics after having served in Congress with Oberstar in the post-Watergate 1970s.

Shortly after midnight, Cravaack called Nolan and then told supporters gathered at Toby's restaurant in Hinckley: "It's been a privilege and an honor to serve the people of the Eighth District.''

For their part, Nolan's supporters could feel momentum building early in the evening. "We're taking things cautiously, we're seeing some returns that give us reason to be happy,'' said Nolan campaign manager Michael Misterek, who was rallying with supporters at the Brainerd Hotel and Conference Center.

The nationally watched contest, which had the potential to influence the balance of power in the U.S. House, drew some $10 million in outside spending from groups representing both sides of the partisan divide.

Cravaack was forced to raise some $2 million on his own, a heavy lift for any first-term House member with little seniority; Nolan, a businessman with deep roots in DFL politics, raised about half as much.

But both campaigns' fundraising efforts were dwarfed by the flood of national money. For Democrats in Washington, the vast district in northern Minnesota, including the Iron Range, represented one of the best opportunities in the nation to win back one of the House seats they lost in the Tea Party wave of 2010. For Republicans, shoring up Cravaack's hold on the traditionally DFL district also was a priority.

Nolan, riding the DFL's traditional advantage in northeastern Minnesota, went into election night with a slight lead in the polls. He was relying on a strong turnout in traditional DFL pockets of St. Louis County, particularly Duluth.

Cravaack could bank on the Republican leanings of the southern half of the district, which stretches to St. Paul's northern suburbs. But in an unusual move for a Republican, Cravaack also made a strong play for union steelworkers on the Iron Range, where he has worked to advance the long-stalled Polymet nickel and copper mine.

Cravaack, a former union airline pilot, also tried to burnish his labor credentials by promoting a federal-state land swap involving the Boundary Waters Canoe Area to facilitate logging and mining. That, along with his support for the Keystone pipeline from Canada and the St. Croix River bridge -- both projects opposed by environmentalists -- won him a rare union endorsement from Local 49 of the International Union of Operating Engineers.

Despite Cravaack's inroads with labor's rank and file -- if not union leaders -- Nolan portrayed him as a loyal Republican foot soldier in Washington, where he supported a GOP budget plan that Democrats say would turn Medicare into a voucher or premium support system.

Facing a district with an aging population, Cravaack argued that the program needs reform to remain solvent. But the Medicare attacks started early in his term, when Democrat-allied groups bought billboard space in Duluth to highlight his vote.

Getting personal

Democrats also sought to paint Cravaack as a Tea Party extremist, noting his opposition to the 2011 debt-ceiling compromise, which many economists said averted a national fiscal crisis.

Cravaack, however, was careful to avoid the Tea Party label, declining to join the House Tea Party Caucus founded by fellow Minnesota Republican Michele Bachmann.

Cravaack also had to fend off questions about the decision of his wife and two young sons to move to New Hampshire last year to be closer to her job as a pharmaceutical executive.

In the final weeks of the campaign, Nolan and Cravaack sparred bitterly over the issue, with Nolan running ads suggesting Cravaack doesn't live in Minnesota.

Cravaack, who maintains a residence in North Branch, succeeded in getting some ads pulled from the air.

The issue became acutely personal when Cravaack revealed that a leading factor in the move was his older son's autism. He accused Nolan of bringing his family into the race. Nolan said the issue was Cravaack's local ties, not his family.

Both candidates sought to portray themselves as closely attuned to the region's North Woods culture. Both Cravaack and Nolan took time to participate in the first day of the firearms deer season, although it was Cravaack who won endorsement by the National Rifle Association.

Cravaack also counted on the support of social conservatives -- many of them Democrats in northern Minnesota -- by highlighting his position against abortion rights.

Nolan, a Catholic like Cravaack, opposed abortion rights in the 1970s when he was in Congress. But he said he has since decided it should be a personal decision.

Kevin Diaz is a correspondent in the Star Tribune Washington Bureau.