"They think this Senate seat is an auction," Heitkamp often says in campaign speeches, referring to Republicans and groups like Crossroads, which has aired more than $250,000 in ads attacking the Democratic candidate. The seat, Heitkamp adds, "does not belong to Karl Rove and his billionaire friends."
Many of Heitkamp's supporters say her personal touch is what attracts them.
"She gets down to brass tacks, she really talks to voters," said Bill Bohnsack, a 66-year-old retired teacher from Mayville, N.D., who plans to vote for Heitkamp.
Berg, meanwhile, has generally stuck to linking Heitkamp to Democrats in Washington.
"I think it's clear at the national level between policies under President Obama ... she is aligned with him," said Berg, who is part of the 2010 freshman class that handed House control to Republicans.
He says he's just as personable a campaigner as Heitkamp and recounted participating in a parade in the Democrat's hometown in which he had so many GOP supporters in the back of his pickup truck that the floor bottomed out. One of his ads features a testimonial from an Army veteran who says Berg helped him get a Purple Heart military decoration; another focuses on Berg as a young child. It closes with footage of Berg and his 12-year-old son, Jack.
"North Dakota is a small state, we know people, we know each other," Berg said in an interview. "And I think this election will be won with grass-roots, person-to-person campaigning."
But warmth is not all that matters to voters here.
Tracton Lewis and his wife, Victoria, both 35, said they thought Berg was plenty friendly. But they drove from their home in Park River, N.D., to Fargo to hear Berg speak for one reason.
Heitkamp, Tracton Lewis said, "is too liberal for us."
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