Today, Minnesota Democratic Rep. Rick Nolan announced he would retire at the end of his second three-term stint in the House (his first was between 1974 and 1980), giving Republicans fresh optimism in an Iron Range district that voted for President Trump 54 percent to 38 percent in 2016. But Nolan was already the most vulnerable Democratic incumbent in the country, and we're keeping our Toss Up rating for now.

Despite the union-heavy Iron Range's hard swing into the Trump column, Barack Obama won the district twice and Democrats have a deep bench of local DFL officeholders who could be strong contenders. Former FBI analyst Leah Phifer had been mounting a primary against Nolan based on his openness to new mining rights, but now the April 14 DFL convention could draw a crowd.

Meanwhile, Republicans have touted St. Louis County Commissioner Pete Stauber's bid for months, but the former police officer and minor league hockey player entered 2018 with just $137,000 on hand, calling into question his viability. Wealthy outdoor store businessman Stewart Mills III, who had declined a third

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