Biden, Trump win Michigan primaries, edging closer to November rematch

US President Joe Biden and former president Donald Trump have won the Michigan primaries, further solidifying the all-but-certain rematch between the two men for the White House.

Biden defeated Minnesota Rep. Dean Phillips, his one significant opponent left in the Democratic primary. But Democrats were also closely watching the results of the "uncommitted" vote, as Michigan has become the epicentre for dissatisfied members of Biden's coalition that propelled him to victory in the state — and nationally — in 2020.

As for Trump, he has now swept the first five states on the Republican primary calendar.

His victory in Michigan over his last major primary challenger, former UN ambassador Nikki Haley, comes after the former president defeated her by 20 percentage points in her home state of South Carolina on Saturday.

The Trump campaign is looking to lock up the 1,215 delegates needed to secure the Republican nomination sometime in mid-March.

Both campaigns are watching Tuesday's results for more than just whether they won as expected.

For Biden, a large number of voters choosing "uncommitted" could mean he's in significant trouble with parts of the Democratic base in a state he can hardly afford to lose in November.

Trump, meanwhile, has underperformed with suburban voters and people with a college degree, and faces a faction within his own party that believes he broke the law in one or more of the criminal cases against him.

Biden has already sailed to wins in South Carolina, Nevada and New Hampshire.

The New Hampshire victory came via a write-in campaign as Biden did not formally appear on the ballot after the state broke the national party rules by going ahead of South Carolina, which had been designated to go first among the Democratic nominating contests.

Both the White House and Biden campaign officials have made trips to Michigan in recent weeks to talk with community leaders about the Israel's bloody war in Gaza and how Biden has approached the conflict, but those leaders, along with organisers of the "uncommitted" effort, have been undeterred.

That push, which began in earnest just a few weeks ago, has been backed by officials such as Democratic Rep. Rashida Tlaib, the first Palestinian American woman in Congress, and former Rep. Andy Levin.

Our Revolution, the organising group once tied to Sen. Bernie Sanders, I-Vt., had also urged progressive voters to choose "uncommitted", saying it would send a message to Biden to "change course NOW on Gaza or else risk losing Michigan to Trump in November."

Trump goes full throttle

Trump's dominance of the early states is unparalleled since 1976, when Iowa and New Hampshire began their tradition of holding the first nominating contests.

He has won resounding support from most pockets of the Republican voting base, including evangelical voters, conservatives and those who live in rural areas. But Trump has struggled with college-educated voters, losing that bloc in South Carolina to Haley on Saturday night.

Even senior figures in the Republican Party who have been skeptical of Trump are increasingly falling in line. South Dakota Sen. John Thune, the No. 2 Senate Republican who has been critical of the party's standard-bearer, endorsed Trump for president on Sunday.

Still, Haley has vowed to continue her campaign through at least Super Tuesday on March 5, pointing to a not-insignificant swath of Republican primary voters who have continued to support her despite Trump’s tightening grip on the GOP.

The Republican Party is also aligning behind Trump as he continued to be besieged with legal problems that will pull him from the campaign trail as the November election nears. He is facing 91 criminal changes across four separate cases, ranging from his efforts to overturn the results of the 2020 presidential election, which he lost, to retaining classified documents after his presidency to allegedly arranging secret payoffs to an adult film actor.

His first criminal trial, in the case inv olving hush money payments to Stormy Daniels, is scheduled to begin on March 25 in New York.