GOP Rep. Dan Benishek's retirement gives Democrats an opportunity to get back into Michigan's Upper Peninsula, a Democratic stronghold until Benishek's 2010 election. Chip Somodevilla AFP/Getty

Democrats face long odds and a map that's stacked against them in their quest to regain the House majority. But GOP Rep. Dan Benishek’s retirement last week highlighted the sort of conservative-tilting district that Democrats need to capture to take back power in Congress.

Benishek’s seat in Michigan’s Upper Peninsula was a Democratic stronghold for nearly two decades, when Rep. Bart Stupak held the seat and nearly always won reelection easily. But Benishek captured it when Stupak retired in 2010, and he held it in a tough race as Mitt Romney carried the district’s votes in 2012.

Now, Benishek’s retirement gives Democrats their best opportunity yet to expand back into Northern Michigan. It’s one they need: Democrats are 30 seats shy of the House majority, but House Republicans hold only 26 seats that President Obama carried. Democrats have to expand back into more conservative-leaning territory in order to win the House. That’s part of the reason why analysts say such an outcome is so unlikely in 2016, but it’s also why the party is preparing to focus on the race to replace Benishek.

Democrats are already coalescing around a favored candidate: former state party chairman Lon Johnson, who has been endorsed by Michigan’s Democratic members of Congress and whose wife, Julianna Smoot, was a deputy campaign manager and high-powered fundraiser for President Obama. Democrats’ 2014 candidate, Jerry Cannon, is running again, but the Democratic Congressional Campaign Committee has repeatedly singled out Johnson for praise, though he is not from the district. Johnson has a home in the area, but the GOP has tagged him as a carpetbagger.

The more pressing concern for Democrats might be whether voters identify Johnson, whose family connection to the region dates back five generations, as a local Democrat or a national one. Stupak, the last Democrat to represent the district, toed a more conservative line than other members of his party, memorably holding out on supporting Obamacare until the last minute over concerns regarding public funding for abortion. The National Republican Congressional Committee plans to use Johnson’s time at the Michigan Democratic Party to make that case.

“We’re going to hang [the] Michigan Democratic Party platform around Lon Johnson’s neck, and I think that will sink his campaign,” said National Republican Congressional Committee spokesman Chris Pack.

Still, his campaign concerns some local Republicans. “I fully expect Lon Johnson to be the next congressman,” said Randy Bishop, the chairman of the Antrim County GOP. “He has $6 million of Obama’s money.”

Johnson himself signaled that his campaign will have plenty of resources. “We’re going to continue to build the momentum that’s going to be required to win,” Johnson said. “We will have the necessary funds to be competitive throughout this campaign.”

A handful of Republican candidates have confirmed interest in running to replace Benishek, but none offered a time table for when they might announce a decision. Michigan Republicans named state Sen. Tom Casperson and former state Sen. Joe Allen as likely favorites for their nomination. (Allen ran in 2010 but lost the primary to Benishek by a mere 15 votes.) State Rep. Peter Pettalia and state Sen. Wayne Schmidt could also be in the mix.

Bill Ballenger, the founder of Inside Michigan Politics, said that both Casperson and Allen are “aggressive campaigners” who would be better candidates than Benishek, who barely won reelection in 2012. “For Benishek to be gone, I don’t think that necessarily helps that much,” Ballenger said of Democrats’ odds in the district. “Benishek was never particularly a strong general-election candidate.”

Michigan GOP chairwoman Ronna Romney McDaniel isn’t worried about Democrats’ slight head start in the race. “There’s plenty of time for whoever our candidate ends up being to get to know the district. I’m not concerned about the timing. Whoever runs needs to understand uniqueness of the area, especially U.P. [Upper Peninsula].”

That’s what makes the district such an enticing target for Democrats and a potential foothold in districts around the country where the party has receded since the 2010 Republican wave. At this early stage, Democrats are planning to make the most of the opportunity.

“We’re going to be investing a lot of resources and field operation in getting out the vote,” said Brandon Dillon, chairman of the Michigan Democratic Party. “We’re happy the situation has changed … and ready to take advantage of it.”

CORRECTION: The original version of this story misidentified Johnson's property in the district. It has been his residence since 2011.

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