Sen. Bernie Sanders speaks during a campaign rally as his supporters cheer him on Tuesday in Miami. | AP Bernie Sanders' Rust Belt rebound The senator's Michigan win is a red flag for Hillary Clinton.

Bernie Sanders re-energized his presidential bid Tuesday with a told-the-establishment-so upset victory in Michigan — a foreboding sign for Democratic front-runner Hillary Clinton, who could face a similarly potent strain of economic populism in a general election match-up against Donald Trump.

In narrowly winning the first big industrial state to vote, Sanders demonstrated that his economic message reverberates in the Rust Belt and, for the first time, proved he could win in a racially diverse state.


But the victory did little to budge the overall delegate math of the race that has narrowed his path to the nomination – Clinton’s campaign downplayed the loss by noting that she widened her overall delegate lead by more than 12 thanks to a landslide victory in Mississippi.

More worrisome for Democrats was the unfolding scene of a pugnacious populist trouncing Clinton among white, working-class voters who feel left out amid an uneven economic recovery, a seeming red flag for Clinton, who could end up facing another candidate riding high in the Rust Belt -- Trump carried Michigan by winning 37 percent Tuesday -- after tapping into deep voter discontent.

Now “both candidates have an incentive to continue engaging in a race to the top on economic populism issues,” said Adam Green, co-founder of the Progressive Change Campaign Committee.

The next front in the Democratic fight over trade policy and economic inequality will take place March 15, when two industrial Midwestern states -- Ohio and Illinois – cast votes in primaries that could either alter the trajectory of the Democratic primary or all but end it.

Sanders' win Tuesday supplied his supporters with a new tank of oxygen after a series of thumping losses in the South. “The Beltway elite may never have really understood why job-killing trade deals are such a big deal,” crowed Dan Cantor, national director of the Working Families Party. “But the people of Michigan surely do, and Bernie Sanders does too.”

Sanders’ big win also counted as his high-water mark among black voters --- Clinton beat him among African-American voters 65 to 31 percent, according to exit polls, showing he has made more inroads with African-Americans in the Midwest than in the South, where he suffered drubbings among black voters in states like Alabama, Arkansas, Georgia, South Carolina, Tennessee and Virginia. On Tuesday night in Mississippi, Clinton crushed him 89 to 11 percent with black voters.

In Michigan, Sanders ran competitively in Genesee County, home of Flint, a largely African-American city suffering through a water crisis that Clinton has been making a focal point of her campaign over the past month. She racked up the endorsements of a group of ministers from Flint and even asked her own campaign volunteers to distribute water to residents of the troubled city instead of canvassing for votes.

The Midwestern vote of confidence for Sanders means the candidate who insisted he wasn’t giving up until June will now have fewer naysayers beginning the drop-out drumbeat.

“The back end of the calendar is good for us, and the South is over now,” said Sanders top strategist Tad Devine. “There’s no more states touching Arkansas that are available.” Sanders expects to gain momentum out of the West in states like Idaho, Arizona and Washington state, Devine said, before moving to the biggest battlegrounds in New York and New Jersey, and then California in June.

Sanders’ campaign operatives and allies said they were truly surprised by the upset win Tuesday night. “If we have a near win today, that’s pretty good in our book,” Devine told POLITICO as the polls closed, before results were in. An outright win, he said, “would be unbelievable.”

With 25 percent of the votes still being tallied at 11 p.m., Sanders appeared on television to declare the evening “an enormously successful night” in which he “repudiated the pundits who said Bernie Sanders was not going anywhere.”

Michigan was always a state where Sanders operatives thought his economic message would resonate, even though recent polls showed him trailing by double-digits. An open primary state, Michigan fit the mold of Sanders-friendly terrain -- Clinton ended up losing by 42 points among independent voters, but won by 16 points with registered Democrats. Another plus for Sanders: the majority of voters outside of urban centers like Detroit are working class and white.

In recent days, Sanders blanketed the airwaves with ads attacking Clinton’s record on trade, and he gave speeches tying trade policy and agreements like NAFTA, signed into law by Bill Clinton, to the loss of manufacturing jobs in Michigan and, in particular, Detroit.

Some Democratic strategists said despite the excitement surrounding Sanders’ Michigan win, it may not prove to be a harbinger of what’s to come.

“[Clinton] is rolling in Florida, and has a big lead in Illinois,” said former Obama strategist David Axelrod. “The two largest states are up next week and she already has a larger lead among pledged delegates than Obama ever had in ‘08. Bernie has run a great race. But by the time next week is done, she may have a lead in pledged delegates that, with the proportional system, will be very, very hard to overturn.”

But even so, the victory increased Sanders’ value as one of the few leading figures who will be able to help unite the Democratic Party to stop Trump -- Clinton allies said they still felt confident that Sanders backers would eventually fall in line behind Clinton when faced with the threat of the GOP front-runner. But that is unlikely to happen without help from Sanders himself -- and now, that help is unlikely to come until much later in the calendar.

Clinton operatives had hoped that a surprise attack on Sanders in the Flint debate Sunday night -- arguing that he “was against the auto bailout” -- would serve as a finishing move, landing just before voters headed to the polls. But the attack only told part of the story — Sanders voted for the 2008 auto bailout as a standalone bill which failed. But he voted against using the TARP funds to bail out the auto industry because those funds would also bail out financial institutions.

Clinton allies in Ohio said they still expected the auto bailout message to move the needle there even as Sanders camp pushed back.

“The fact that he voted against the very important components of the auto rescue package -- that’s gotten back to voters who are now starting to pay attention,” said Ohio Rep. Tim Ryan, who is one of the biggest Clinton surrogates in the state. “It wasn’t a knockout blow, but it put him on the ropes. It really came out of nowhere -- she’s been talking about manufacturing and to say directly that Bernie voted against the help for one in every eight jobs in Ohio? You can talk about theory and ideology but when you start talking about pocketbook issues, people start making decisions on that.”

But Devine called the auto bailout punch a “desperate last-minute move by them” that ultimately hurt Clinton with voters. And he predicted in the long term it would do more harm than help. “Don’t attack him on something that is not true,” Devine said, “especially if your main problem is credibility.”

