Ex-Sen. Al Franken isn't the only Minnesota politician who had to resign over complaints of sexual misconduct. Two of the state's legislators -- one Republican and one Democrat -- resigned on the same day in November amid sexual harassment allegations.

Their exits triggered special elections for Feb. 12. This month, 10 states -- including Minnesota -- will hold special legislative elections, several of which are happening because politicians facing harassment allegations have either left office or committed suicide.

Most of this month's special elections are in states where Democrats have no serious chance to undo Republican majorities, such as Louisiana, Missouri and Mississippi. Still, given Democrats' strong performances in special elections since the inauguration of President Donald Trump, the party is hopeful it will make further gains.

"Special elections used to be the backwater of politics," says Daniel Squadron, executive director of Future Now, one of several new Democratic-aligned groups that have sprung up since Trump's election. "They've now become the roaring rapids of the movement for change."

Democrats picked up 16 legislative seats in special elections last year, compared with three for Republicans. Democratic candidates also outperformed Hillary Clinton's 2016 showings in their districts, on average, by double-digit margins.

That momentum for Democrats doesn't appear to be letting up.

On Jan. 16, Democrats flipped a Wisconsin state Senate seat in a district that Trump had carried by a 17 percentage point margin. Republican Gov. Scott Walker described his party's loss as a "wake-up call."

"Democrats are winning on turf that was thought of as impossible," says Michael Davies, a Democratic consultant. "In these specials, there are probably lesser-known candidates, so it can become more of a referendum on what people feel about the president and the party in power."

Republican strategists note that each special election is, well, special. By their nature, they don't feature incumbents who tend to have an advantage. Individual races are more likely to hinge on dynamics specific to the district or the state -- not national trends. 

"There will be dozens of special elections this year," says Matt Walter, president of the Republican State Leadership Committee. "We had five elections in one night in January, and the GOP won four of them. The Democrats suggested, and the media enabled, a narrative of a wave when that simply wasn't the case."

In Minnesota, the downfall of Democrat Dan Schoen has created an opening for the GOP in the state Senate. On Monday, Republican Danny McNamara, a former state representative, won the party's nomination. He will face Democrat Karla Bigham, a Washington County commissioner and former state representative.

"It's a big priority for us," says Matthew Pagano, executive director of the Minnesota Republican Party. "It's a swing district, one that Democrats have narrowly held, but it's one that Trump won."

In the other Minnesota race that resulted from a sexual harassment scandal, the Republican party is expected to hold on to the House seat vacated by Tony Cornish.

Meanwhile, Kentucky is holding two special elections for state House seats this month. One is open because the late Rep. Dan Johnson, a Republican, killed himself after news reports that he allegedly molested a 17-year-old girl.

His widow, Rebecca Johnson, is running to succeed him on Feb. 20. The Democratic candidate is Linda Belcher, who has held the seat off and on since 2008. After winning reelection in 2010, Belcher lost in 2012 then regained the seat in 2014. Dan Johnson narrowly defeated her in 2016, taking 50.42 percent of the vote to Belcher's 49.58 percent.

"We really don't know how the thing is going so far," says Paul Ham, who chairs the Bullitt County GOP. "Right now, we just have a very narrow margin over the registered Democrats."

In Florida, Democrats are hoping they can pick up a Sarasota-area House seat on Feb. 13 that was vacated by Alex Miller, a freshman Republican who said she needed to devote her time to her business and teenage sons.

James Buchanan, a real estate agent and the son of Republican Congressman Vern Buchanan, immediately announced he would seek Miller's seat. He had been running for a neighboring state House seat and brought with him a considerable campaign treasury as well as the backing of numerous prominent Florida Republicans.

But local party officials grumble that the younger Buchanan may have sought to glide in on his father's name and has only recently stepped up his campaigning efforts. He faces Democratic attorney Margaret Good.

"That's become an increasingly competitive part of Florida and those Democrats down there are really well-organized," says Susan MacManus, a political scientist at the University of South Florida in Tampa.

Democrats are vowing to fight everywhere, seeking to chip away at GOP supermajorities where they can't end Republican control.

"We've seen massive Democratic overperformance across special elections, so we're playing offense and, within our priority chambers, investing in special elections even in districts that Hillary lost," says Catherine Vaughan, CEO of Flippable, another new group helping to fund Democratic candidates. 

Special elections remain low-turnout affairs, so political scientists say their predictive value in terms of the general election in November will be stronger for those that happen closer to the midterms. 

Democrats, who have suffered severe losses at the state legislative level over the course of this decade, are hoping that their performance in special elections -- combined with their strong showings in the legislative elections in New Jersey and Virginia in the fall -- will demonstrate that this is the year they can begin seriously rebuilding.

"In 2017, the [Democratic Legislative Campaign Committee] doubled our fundraising and we're on track to spend $35 million in the 2018 cycle," says that organization's executive director, Jessica Post. "We're investing earlier than ever in battleground states and helping state leaders set winning strategies in order to elect more Democrats in state legislatures across the country."