Republicans have been seeing more good news than bad about the upcoming midterms, but they may have gotten a golden gift today. Democratic incumbent Rep. Rick Nolan issued a surprise retirement announcement from Minnesota’s eighth congressional district, an office which Nolan had given every indication he would defend in November. That opens up what might the GOP’s best opportunity for a pickup in November:

Minnesota Rep. Rick Nolan announced Friday he won’t run for re-election, opening up a top targeted seat for Republicans in 2018.

“There is a time and a purpose for everything and now is the time for me to pass the baton to the next generation,” Nolan said in a statement.

The Democratic-Farmer-Labor congressman, who’s serving his sixth nonconsecutive term, represents Minnesota’s 8th District, home to the Iron Range, where President Donald Trump won by 16 points in 2016. Nolan carried the district by half a point the same year.

What does MN-08 look like without an incumbent in the race? The district carries a Cook rating of R+4, even though Chip Cravaack’s win in 2010 was the only GOP win for the district in the last 72 years. All but eight of those years were split between Democrat John Blatnik’s 14 terms and Democrat Jim Oberstar’s 36 years in Washington.

In other words, Republicans haven’t had a lot of opportunities in MN-08, but they have had some. Nolan came back to wrest the district away from Cravaack in the 2012 election with Barack Obama at the top of the ticket, winning by nine points, but only barely eked past Stewart Mills III in the next two elections. In 2016, Nolan only prevailed 50.2% to 49.6% against Mills’ largely self-funded campaign. Nolan’s long relationship with Minnesota voters made the difference, but not by a lot.

The electorate in MN-08 has changed somewhat over the years, but it’s fair to say that Democrats have changed much more dramatically. Just like with the national party, the DFL has transformed from a party of working-class-focused policies to extremist progressivists, including on environmental issues that tend to hit the local mining industry hard. Nolan was able to ride that out by relying on his history, but now any new candidate will wind up having the baggage that comes with all of the radical progressives in the Twin Cities running the party. Trump’s overwhelming draw in this district practically makes it blink red on the Democratic map. And as Gary Gross points out, it’s not the only district in Minnesota to be doing so.

The Republican Party wasted no time in pushing their nominee, Pete Stauber, after the announcement:

“Today’s news of an open seat in Minnesota’s 8th District is yet another boost to Republican prospects in 2018. Minnesota’s 8th District was already a top pickup opportunity in the country for national Republicans, and today’s news positions 8th District Republicans like Pete Stauber, in an even stronger position. We are looking forward to bringing new, Republican representation to Northern Minnesota in November.”

The Star Tribune previews the general-election race. Note well how Nolan’s DFL replacement positioned herself:

[A] spokesperson for the NRCC said Friday that the district is a top priority, and the Minnesota GOP called it one of the biggest pickup opportunities for national Republicans.

The leading Republican candidate this year has been Pete Stauber, a St. Louis County Board member and retired Duluth police officer.

“Minnesota’s Eighth District was already a top pickup opportunity in the country for national Republicans, and today’s news (puts) Stauber in an even stronger position,” read a statement from the state GOP.

On the DFL side, Leah Phifer announced last year that she would challenge Nolan. The former FBI counterterrorism analyst has criticized Nolan for being too friendly to mining interests. A number of current and former elected DFL officials from Duluth, the Iron Range and other parts of northeastern Minnesota are likely to consider the race with Nolan’s exit.

Too friendly to mining interests? Republicans can strike gold here, if they put their backs into it.