One week from now, Sanders may not even win the state.

Even before Sanders’ woebegone Tuesday — marked by losses to Joe Biden throughout the South and in Massachusetts and Minnesota — a Detroit News/WDIV-TV poll put Biden ahead of Sanders by nearly 7 percentage points in Michigan.

Democratic presidential candidate Sen. Bernie Sanders. | Chip Somodevilla/Getty Images

Of voters who had already cast absentee ballots, the outlook was bleaker, with Sanders running behind Biden by nearly 20 percentage points.

And that was before Super Tuesday laid bare the full force of the momentum Biden drew from winning South Carolina, prompting moderate Democrats to coalesce around him and persuading many undecided voters to break his way.

“This thing could be over for all intents and purposes in three weeks,” said Paul Maslin, a top Democratic pollster who worked on the presidential campaigns of Jimmy Carter and Howard Dean. “It’s done unless Joe makes some horrible mistake. He will win blacks 75-25 minimum from here on in. He doesn’t have Hillary’s negatives. And people want to beat Trump big time. This race is over.”

Sanders’ advisers believe Michigan could work in the Vermont senator‘s favor next week, with a victory re-establishing his foothold in the race.

But the signs of weakness were evident everywhere in the results on Tuesday. He not only lost to Biden in the states Biden was expected to win, but also in Texas, Maine, Minnesota and Massachusetts. And Biden didn’t just maintain the support of black voters that powered his victory in South Carolina. He also performed well with suburban whites. Biden won noncollege-educated white voters in eight states Tuesday, compared to four for Sanders, according to exit polls.

The electoral map on Tuesday was expected to favor Sanders. But with the exception of California, he underperformed. Next week’s run of primaries represents a far smaller delegate haul, but Michigan — with 125 delegates — is a critical general election state and an indicator to Democrats of a candidate’s broader appeal. A loss there could significantly undermine his electability argument.

“Biden can finish Bernie off in Michigan,” said Michael Ceraso, who worked for Sanders in 2016 and was Pete Buttigieg’s New Hampshire director before leaving his campaign last year.

Biden, Ceraso said, “understands coalition building is about compromise, which is going to help in Michigan, where the electorate is economically diverse, largely white, with a strong African American voting population.”

Biden has little footprint in the state, and his campaign has reserved just $500,000 in TV ad time there. But he is making new inroads.

Barry Goodman, a Biden bundler in Michigan, said Biden on Monday will attend a fundraiser in the state whose hosts include Goodman, former Michigan Gov. James Blanchard, and Detroit Mayor Mike Duggan.

“Everybody wants to get on the bandwagon now,” Goodman said. “I think if Joe wins [Michigan] by 10, Bernie may not leave yet. But the following weeks, when he loses by 10 in Florida, Mississippi and Georgia, I think it’s done.”

Goodman said he is “getting private emails from people who said, ‘I’ve never done this for president before — given any money. But put me in for a grand, a grand or $2,800 … People are coming out of the woodwork.”

It is possible, in this volatile primary, that Sanders could beat Biden in Michigan — and that the state could mark another turning point in a race that has been defined by them.

On Wednesday, Sanders launched new TV ads in states that vote on March 10 and March 17, including one — playing in Michigan — that features a union autoworker lauding Sanders for his opposition to trade deals and criticizing Biden for his support for them.

The campaign this week promoted endorsements from a group of faith leaders in Michigan, and it pointed to older polling showing Sanders with a lead in the state. Sanders plans to travel to Michigan for rallies Friday in Detroit and Sunday in Grand Rapids.

Sanders’ campaign has long been confident about Michigan, due to his 2016 finish there, as well as his past performances among working-class whites and Muslim voters. In a YouGov poll conducted in mid-February, Sanders led Biden in Michigan by nine percentage points.

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“Sanders’ pro-union message and record of standing up against outsourcing and free trade deals is going to resonate,” said Ro Khanna, Sanders’ campaign co-chair.

In addition to his new ads attacking Biden on trade, Sanders laced into Biden on the issue, without naming him, at his election night rally in Vermont on Tuesday night.

It is unclear how deep a reservoir of support Sanders has carried over in Michigan from 2016. In the midterm elections, Sanders and New York Rep. Alexandria Ocasio-Cortez campaigned aggressively in the state for a gubernatorial candidate, Abdul El-Sayed, who was drubbed by more than 20 percentage points in the Democratic primary. Gretchen Whitmer, the establishment favorite, won.

At the same time, as Sanders’ aides like to point out, Whitmer was happy to have Sanders campaign for her in the general election in 2018. The governor, who was tapped to give the Democratic response to Trump’s State of the Union speech in early February, has not endorsed in the race.

Whitmer’s two-term Democratic predecessor as governor, Jennifer Granholm, announced her support for Biden Wednesday.

Still, after Sanders’ losses Tuesday in states that he won in 2016, such as Maine, Minnesota and Oklahoma, his prospects in Michigan appear to have dimmed.