Updated 3 p.m. | Posted 9:25 a.m.
DFL U.S. Rep. Rick Nolan said Friday he will retire from Congress and not seek re-election this year.
It's a stunning change of heart. In June, Nolan told reporters he would not run for governor because he was feeling pressure to retain his seat in Congress and his constituents wanted him to run again.
"The challenges and consequences of the issues facing our nation in Washington are too important for me to walk away from at this time," Nolan said then.
In a statement Friday, however, after listing his accomplishments, Nolan said, "there is a time and a purpose for everything and now is the time for me to pass the baton to the next generation."
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Nolan's departure has huge political ramifications. The Democrat represents a northern Minnesota district that both parties have fought hard over in recent elections and that President Donald Trump won in 2016.
He was expected to face both a hard-fought primary and a competitive general election campaign if he stuck around.
Nolan, 74, has served six terms in Congress, although that has been split between the 1970s and more recent years. He was elected again in 2012 to represent the 8th Congressional District.
The national Democratic Congressional Campaign Committee Friday vowed to keep the seat in Democratic hands. It's not clear, however, which Democrats will jump in to run.
Leah Phifer, a former FBI analyst and Two Harbors, Minn., native who said in October she would challenge Nolan for the Democratic nomination, reaffirmed on Friday that she is running for the seat.
Phifer said Friday her campaign is already seeing an uptick in fundraising.
"We're just really excited," she said. "We're doing a lot of outreach today connecting with a lot of people and making sure that we are carrying forth our grassroots message that we've had all the way from the beginning."
Duluth Mayor Emily Larson and her predecessor, Don Ness, both ruled out a run. Tony Sertich, another well-known northern Minnesota Democrat who served in the Legislature, said Friday he has "zero interest."
State Rep. Jason Metsa, DFL-Virginia, is weighing a bid. And former state Rep. Joe Radinovich, currently chief of staff to Minneapolis Mayor Jacob Frey, is "strongly considering" a campaign.
The Republican Party of Minnesota called Nolan's decision not to seek re-election a boost to GOP prospects.
Right now, St. Louis County Commissioner Pete Stauber of Hermantown, Minn., is the sole Republican candidate in the race after two-time Nolan challenger Stewart Mills passed on a run.
Stauber said he's still focused on running a campaign on the issues that matter from mining to military readiness.
It's unclear if Mills will stay on the sidelines, although national Republicans have rallied around Stauber, who is also a Duluth police officer. On Twitter Friday afternoon, Mills said he was "very seriously considering another run" for the seat but had no timeline for a decision.
The district is also home to Minnesota Republican House Speaker Kurt Daudt. He has been spending plenty of time on the Iron Range promoting two big mine projects and other parts of the district talking about pipelines.
The Minnesota 8th is enticing to Republicans because they've held it within the past decade and came close to winning the seat back from Nolan after he reclaimed it for Democrats in 2012.
It's also one of a small number of Democratic-held congressional districts in the country that President Trump won in 2016, which he did by 56,000 votes.
Eighth District Republican Party Chair Ted Lovdahl has higher hopes with Nolan out of the way.
"It makes a substantial difference," he said, "because he had his followers and now they're gone and they're gonna be 'What do I do now, you know?'"
But Lovdahl acknowledges it cuts both ways for Stauber. "I wouldn't be surprised if there's some more Republicans jump in. I wouldn't be surprised at all."
MPR News reporters Dan Kraker and Mark Zdechlik contributed to this report.