To that end, the result was a warning sign for a leader already struggling with record-low approval ratings, concerns about his age and political troubles like the US border crisis.
After all, Michigan, along with the swing states of Pennsylvania and Wisconsin, are part of the so-called “blue wall” that Biden needs to uphold to return to office.
The greatest unknown is what these voters might do in the general election in November.
Will some people choose not to participate in the competition? Will some vote for a third party candidate? Or will some turn to Trump, just as they did eight years ago?
Asked about this after the polls closed, she heard Michigan State Press Secretary Leila El-Abd — the sister of Democratic Congresswoman Rashida Tlaib — admit that Trump, who imposed a Muslim ban as president, wasn't exactly a “friend” of their cause.
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But she said disengaged voters were not a monolith either, and “they will have to vote their conscience” in the general election.
“There will be groups of voters within this movement that already feel deeply betrayed by Biden and his administration that Muslim Americans and Arab Americans have been directly impacted by Israeli aggression and collective punishment of Palestinians,” she said.
“And not only that. As Democrats, we feel betrayed, so why would we risk our democracy to side with someone like him [Israeli leader Benjamin] Netanyahu and his right-wing government?
The good news for Biden is that there are still several months between now and the election, and in a country as unpredictable as America's divided states, anything can happen.
Republicans held their primary contest in Michigan as well, and while Trump won resoundingly over Nikki Haley, she still had more than 162,000 votes with just over half of the total votes counted.
If these voters don't want Trump, where will they go in November?
Regarding the conflict in the Middle East, the White House insists that it is doing everything it can to push for a ceasefire.
That may be so, but the president clearly has some work to do to restore the same alliance that helped him get to the White House in the first place.
As Trump marches on, and as voter anger and apathy become a real danger in an electoral rematch that few Americans seem to want, nothing can be left to chance.
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