Jessica Rinaldi / Reuters

Timing may be everything in politics, but it hasn’t been kind to Russ Feingold. When the former—and perhaps future—Wisconsin senator was supporting gay marriage and railing against corporate welfare, trade deals, the Iraq War, and the Patriot Act, his was a lonely voice in the Democratic Party. And in 2010, just a few months after the Supreme Court gutted his signature legislative achievement, he faced off against a Tea Party-aligned plastics executive named Ron Johnson in the midst of a Republican wave. Feingold lost an election he surely would have won had it occurred two years earlier or later.

In announcing Thursday that he would seek a rematch against Johnson, Feingold, 62, is betting that his timing will finally be right in 2016. With Feingold’s brand of progressive populism having ripened into a consensus among Democrats, it’s a pretty decent gamble—at least as things stand a year-and-a-half out from the election. For starters, unlike in 2010 he’ll be running in a presidential-election year, and the Democratic nominee has carried Wisconsin every four years since 1984. He shouldn’t have a messy primary to win, as both the party establishment and progressive activists celebrated his entry into the race. The Senate Democrats’ campaign arm immediately endorsed him, and both the Progressive Change Campaign Committee and their favorite Democratic senator, Elizabeth Warren, sent out rapid requests for money to their email lists. Finally, while Johnson now has the advantage of incumbency, Feingold begins the race leading in the polls: A Marquette University survey last month found that the Democrat had a whopping 16-point lead over Johnson among registered voters.

Wisconsin is sometimes described as a swing state because its elections are close, but its politics tend to be more bipolar than bipartisan—deep red or deep blue, but rarely in the mushy middle. In the last six years, voters in the Badger State have elected Johnson, and backed conservative Governor Scott Walker in three elections; but they also sent liberal Tammy Baldwin to the Senate in 2012. They’ve sent Paul Ryan to Congress but rejected him as vice president, and the same Marquette poll that showed Feingold in the lead also found that Wisconsin voters support Hillary Clinton over their newly reelected governor in the presidential race.

Feingold lost to Ron Johnson in 2010. (Allen Fredrickson / Reuters)

It’s hard to believe that the national Democratic Party’s populist turn has occurred without Feingold. In embracing his candidacy, the PCCC said he would be “another bold ally” by Elizabeth Warren’s side. Yet in some ways, Feingold was Warren before Warren. When he last served in the Senate, Feingold was the only Democrat to vote against the final version of the Dodd-Frank Wall Street reform bill, saying it was too weak. Warren was then still working under President Obama to get it implemented. Now as a senator from Massachusetts, it is she who has emerged as the champion of the progressive base and the sharpest thorn in the president’s side.

As David Graham noted earlier this year, Democrats have a fresh-face problem in 2016—as in, they don’t have many of them. Clinton will most likely be leading their ticket, and some of the party’s top Senate recruits—Feingold, Ted Strickland in Ohio, Joe Sestak in Pennsylvania—are retreads. Feingold’s biggest vulnerability is that, like Clinton, he spent part of his years out of office far removed both from his home state and U.S. politics in general. In 2013, Secretary of State John Kerry sent him to Africa as his special envoy to the Great Lakes region, a post he resigned this February to prepare for the Senate run. Republicans are already tagging Feingold as out of touch, noting that although he filmed his announcement video from his Wisconsin home, he was in California teaching a college course at Stanford when it came out. (Update: Democrats said the GOP was incorrect and that while Feingold teaches his class on Wednesday evenings, he was back in Wisconsin by Thursday and tweeted a picture of himself at home.)

Democrats are banking on Feingold. As National Journal points out, they have little hope of taking back the Senate in 2016 if Feingold doesn’t win. Johnson has been preparing for the rematch, too; he’ll never be mistaken for a centrist, yet he hasn’t been quite the firebrand he was during his campaign or his first years in the Senate. The last time a former senator successfully avenged his loss six years later against the man who defeated him was in 1934. History might not be on Feingold’s side next year, but for once, timing might be.

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