Joe Biden has won the Democratic primary in Michigan – but a concerted effort by anti-war activists to vote “uncommitted” in the race could overshadow his win.

Related: Michigan primary to test Biden among key voting groups in swing state

The US president faced no real primary challenger in the contest. But a campaign that formed just weeks before the primary to vote “uncommitted” in protest of his continued support for Israel’s war in Gaza signaled the deep level of fury and betrayal some Arab American and younger voters in the state feel for Biden.

The group pushing for voters to choose “uncommitted” – called Listen to Michigan – set the goal of 10,000 uncommitted votes in the primary, roughly the same margin that Biden won Michigan by in 2020. With only 14% of the votes tallied, “uncommitted” had received nearly 20,000 votes. For context, when the then president, Barack Obama, ran uncontested in the 2012 race, about 21,000 voted “uncommitted” against him in that state’s primary, with about 194,000 voting in total.

It isn’t clear what share of “uncommitted” voters are prepared to abandon Biden in the general election this November, when he will most likely face Donald Trump – who is campaigning on a pledge to reinstate and expand his Muslim travel ban.

This campaign is especially significant in Michigan given the state’s large Arab American population, a group that supported Biden strongly in 2020. That support has eroded in recent months.

The Listen to Michigan campaign was intended as a warning for Biden to revise his so far unwavering support for Israel’s campaign in Gaza, which has killed nearly 30,000 Palestinians, ahead of the general election. And Muslim and Arab American community organizers in Wisconsin, Minnesota, Arizona, Florida, Georgia, Pennsylvania and Nevada have already mobilized against Biden in a campaign organizers called #AbandonBiden.