President Joe Biden won the Democratic presidential primary in Michigan with ease on Tuesday.

Biden’s victory was expected, since the president no longer has any major Democratic primary challengers.

U.S. Rep. Dean Phillips’ campaign appears to have peaked in New Hampshire, where Biden was not on the ballot yet still won more than 60% of the vote as a write-in candidate.

Phillips, a Minnesota Democrat, had planned to develop momentum with a solid showing in Michigan, but earlier this month he announced that his fundraising had failed to take off and he was laying off most of his campaign staff. He still plans to remain in the running in states where he has qualified for the ballot in order to provide an alternative for Democrats and Democratic-leaning independents who share his view that Biden is incapable of defeating former President Donald Trump in November’s general election.

Biden’s victory in Michigan marks an important milestone for Biden. The president had instructed the Democratic National Committee to move up Michigan’s place on the presidential primary calendar precisely because of the state’s diversity and its pivotal role in general elections for the presidency.

Biden has much to campaign on in Michigan, a manufacturing-heavy state that could see outsized gains from the president’s bills funding infrastructure improvement, seeding a domestic microchip industry and investing in clean-energy development. The United Auto Workers union, which remains influential in the state, endorsed Biden in January after refusing to join in the AFL-CIO labor federation and other unions’ joint endorsements of Biden in June.

It surely made a difference that Biden joined striking UAW workers on the picket line in September during its historic strike against the “Big Three” U.S. automakers.

“You look at Donald Trump ― every time he’s had the opportunity, he blamed the American worker,” UAW President Shawn Fain said in a Biden campaign video of a conversation with Biden in early February. “And you look at President Biden, every time he’s had the opportunity, he bet on the American worker.”

Notwithstanding Biden’s primary victory on Tuesday, however ― and all-but-certain hold on his party’s presidential nomination in June ― he faces challenges in the Great Lakes State as well.

Biden is either tied with or trailing Trump in public polling in the state.

He must also contend with a restive Democratic coalition in Michigan, where the state’s large Arab American population is in open revolt over Biden’s support for the Israeli war in Gaza. Arab Americans in metropolitan Detroit organized the Listen to Michigan campaign encouraging Michiganders to vote “uncommitted” as an expression of discontent with the Biden administration’s support of Israeli military action.

Perhaps with Listen to Michigan in mind, the Biden campaign and its allies have downplayed the significance of the primary contest.

“They’re really organizing and looking toward the general election,” Jill Alper, a Detroit-area Democratic strategist, told HuffPost on Monday. “Obviously the primary is tomorrow, but the president has been coming to Michigan throughout his tenure as president.”

Likewise, Biden campaign surrogates have been playing up expectations of a strong showing for Listen to Michigan in what appeared to be an effort to diminish expectations for his performance.

“Today I anticipate that we will see a sizable number of people vote ‘uncommitted,’” Michigan Gov. Gretchen Whitmer said Tuesday on MSNBC’s “Morning Joe.” “As we know, our huge Arab, Palestinian and Muslim communities are going to voice some of their opinions with regard to how we’re handling what’s happening over in Gaza and Israel.”

Biden, who faces concerns about his advanced age and the related issue of mental acuity, did not campaign extensively in Michigan ahead of the primary. A rally Biden held with members of the UAW on Feb. 1 was Biden’s first stop in Michigan this year. He has not returned since, but Vice President Kamala Harris and other top administration officials have since visited.

The Biden campaign has also been advertising in Michigan as part of a February-March blitz targeting key demographic groups in several key states. A one-minute spot airing through March 5 in Michigan, Wisconsin and Pennsylvania ― states with large Polish American and northeastern European populations ― blasts Trump for suggesting that he would “walk away from” the North Atlantic Treaty Organization. And a pair of ads set to air on Black radio shows in Detroit and other swing-state cities with large Black populations tout the diversity of Biden administration officials and other accomplishments for Black Americans.

In addition, the Michigan Democratic Party made more than 100,000 voter contacts through door knocking, phone calls and text messages ahead of the state’s Democratic presidential primary.

“President Joe Biden and Vice President Kamala Harris were elected because they promised to deliver for Michigan’s families, workers, and communities — and they kept their promises by bringing manufacturing back to our state, creating hundreds of thousands of good-paying union jobs, and bringing down health care costs for our families,” Michigan Democratic Party Chair Lavora Barnes said in a statement to HuffPost.

Indeed, Biden’s secret weapon in the Great Lakes State is the strength of the Michigan Democratic Party, which was laying the groundwork for a strong November showing long before the Biden campaign got off the ground. In 2017, under Barnes’ leadership, the Michigan Democratic Party launched Project 83, placing one full-time political organizer in each of the state’s 83 counties.

The state party is a “well-oiled machine right now,” said state Senate Majority Whip Mallory McMorrow, whose 2018 defeat of an incumbent Republican typified the party’s Trump-era gains in suburban Detroit. “And I don’t know that that’s something you could have said 10 years ago.”

Michigan Democrats’ performance in the 2022 midterm elections attested to the success of their party-building strategy. Whitmer not only won reelection by more than 10 percentage points, but Democrats also flipped both state legislative chambers, putting the state under unified Democratic control for the first time in four decades. Whitmer and the legislature went on to pass a raft of liberal reforms that would have been unthinkable in previous years: overturning the state’s anti-union “right-to-work” law; repealing an abortion ban from 1931; and requiring the state to get 100% of its energy from clean sources by 2040.

McMorrow predicted that the state’s down-ballot Democrats could provide “reverse coattails” for Biden in November.

“Michigan, on the state level, is the example right now, and I think that’s the story that we’re really excited to tell,” she said.

That story could be easier to tell voters precisely because the Michigan Republican Party has veered sharply to the right in the past year under the leadership of hardcore MAGA Republican Kristina Karamo. Karamo’s refusal to interact with longtime donors from the business wing of the party has brought the party’s finances to the brink of collapse.

Currently, Trump is trying to replace Karamo with former Rep. Pete Hoekstra, another Trump ally who promises to revive the party’s fundraising apparatus and organizational integrity.

But Karamo supporters are passionately fighting the outside rescue effort.

“I don’t think [Trump] should be involved in state politics to begin with,” Steve Willis, chair of Michigan’s Clinton County Republican Party, told The Associated Press.