This week, Montana GOP Rep. Greg Gianforte filed to run for governor in 2020, becoming the third House Republican to announce he won't seek reelection next year. Ordinarily, Republicans might be very concerned about an opening in a seat their candidate carried by just five points in both a 2017 special and a 2018 general election. But both races featured a great political environment for Democrats and the polarizing Gianforte, and 2020 could be a different story. Former Democratic state Rep. Kathleen Williams, who raised $4 million and held the self-funding Gianforte to a 51 percent to 46 percent victory in 2018, is running again and is the early primary favorite over EMT and state Rep. Tom Winter. Last fall, the Bozeman-based Williams benefited from Gianforte pleading guilty to assaulting a reporter, but lacked the kind of rural appeal that allowed Democratic Sen. Jon Tester to prevail statewide. The Republican field is wide open and could include former state Auditor Matt Rosendale, who fell short against Tester by three points and led a February poll of a hypothetical congressional primary

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