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The Montana special election race for the House seat vacated by Interior Secretary Ryan Zinke is "closer than it should be," said the Republican candidate, Greg Gianforte.

In what is turning out to be "a recurring nightmare" for Republicans, Democratic challenger Rob Quist is doing unexpectedly well in the deep red state, Politico writes. The special election will be held Thursday, and while Gianforte has led the polls, Quist recently cut the distance between them to single digits.

"The fact that we're talking about Montana — a super red seat — is amazing," said John Lapp, the former director of the Democratic Congressional Campaign Committee. "It's also amazing how much money Republicans have to pour into these seats to defend them. It's still a steep climb in Montana, but we know that the reaction there means that there's a tremendous amount of Democratic energy across the country, a tremendous amount of fundraising that will then feed into races that are much fairer fights."

The state is an uncomfortable repeat of close, but ultimately Republican-won, special elections in Kansas and Georgia (in the latter, a second run-off, favorable to Republicans, will be held in late June). "Gianforte has an edge, but it's not going to be a slam dunk," a national GOP strategist told Politico.

And while Gianforte, a multimillionaire, has vowed to "work with Donald Trump to drain the swamp and make America great again," his rival has campaigned in recent days with Sen. Bernie Sanders (I-Vt.). "We're already eating ramen in a 500-square-foot family housing apartment, the four of us," one Quist supporter, Mychiel Rauch, 27, told The New York Times. "Gianforte doesn't represent me at all."

"Special elections shouldn't be taken in a vacuum," writes Paul Blest at The Week. "These elections help build the framework of a progressive movement in places long ignored by the national party, are a litmus test for the power of the base, and can be an indicator of where efforts should be focused for the next general election."