MINNEAPOLIS (WCCO) — One of the most expensive and competitive races in the country is in northern Minnesota.

Overall spending on this race between Stewart Mills and Rick Nolan has topped $21 million. Mills and Nolan have collectively spent more than $5 million.

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One reason is the district is so contested is it has flipped back and forth from Democrat to Republican and back to Democrat in recent years. The two faced off in 2014 there were 270,000 votes cast, with Nolan winning by less than 4,000 votes.

Mills says this year will be different.

The Mills campaign party is at Gull Dam Brewing Company in Nisswa Tuesday night. Despite all the money being poured into the race on both sides, it’s still considered too close to call.

Mills says he’s confident he can make up the 1.4 percent margin he lost to Nolan by in 2014. The difference? Donald Trump has had a strong showing in the 8th District, and Mills’ supporters are hoping that carries over.

Former GOP Sen. Norm Coleman’s super pact also pledged several million dollars to help Mills. This was the No. 1 race in the nation when it comes to outside money at one point.

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Mills said he is expecting a tight race when results start coming in, but is hoping it’s one that ends in a victory.

Meanwhile in Baxter, Nolan is spending his night at the Arrowwood. His campaign is expecting the night to be a barn-burner, a nail-biter.

The Iron Range is going to be key in this race, and that’s where Nolan has been spending an awful lot of time campaigning. He’s been playing to the steelworkers and emphasizing the trade agreement with Iron Range jobs.

Nolan also got support in a key visit from Vice President Joe Biden less than two weeks ago. Nolan held his final rally Tuesday morning at the Duluth Labor Temple. He said he feels confident and that’s because the district has seen extremely high voter turnout. That typically favors Democrats.

Minnesotans have no doubt seen the barrage of TV spots from both sides. It’s the most expensive congressional race in the country – with much of the money coming from outside the state.

Nolan says if he returns to Congress for his third straight term, campaign finance reform will be a top priority.

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“Corporations are not people, and money is not free speech and not what democracy is all about,” he said. “It’s about a competitive atmosphere, where everybody can advance their ideas, have arguments debated and voted upon. That’s how you find common ground.”