President Joe Biden and his Republican predecessor Donald Trump both won their respective Michigan primaries on Tuesday, further cementing the likelihood of an unpopular rematch between the 2020 candidates come November.

       But despite Mr Biden’s comfortable victory, Democrats will have been closely watching the extent of the “uncommitted” vote on Michigan ballot papers, as the Great Lakes State became a focal point for discontent among the same voters who propelled the president to victory four years ago, with his unrelenting support for Israel’s actions in Gaza a principle cause of disquiet among many.

       The number of “uncommitted” votes has already surpassed the 10,000-vote margin by which Mr Trump won Michigan in 2016, according to the AP, surpassing a goal set by the organisers of this year’s protest effort.

       Despite underperforming, Mr Trump once again soared to victory over former UN ambassador Nikki Haley in the GOP contest.

       His challenger has insisted on staying in the contest for Super Tuesday on 5 March, even after losing in her home state of South Carolina and Saturday and the support of the imporant Charles Koch-led conservative donor movement.