Kalamazoo (United States) (AFP) - Kamala Harris and Donald Trump battled for holdout votes over the penultimate weekend of campaigning across US swing states, with Michelle Obama to join the Democrat onstage before the Republican nominee hosts an eyebrow-raising rally in New York.

With just 10 days left in a bitterly contested presidential race, the rivals converged Saturday on Michigan, one of the three “Blue Wall” states – along with Wisconsin and top prize Pennsylvania – that Democrats see as critical to Election Day victory on November 5.

Polls show a dead heat in the race’s final days, and with more than 38 million people nationwide already casting early ballots, Americans are deciding whether to elect the country’s first-ever woman president, or its oldest commander in chief.

Part of Harris’s strategy is to peel moderate Republicans away from an increasingly vituperative Trump, who continues to demean some Americans as the “enemy.”

The former president still refuses to accept his defeat at the polls four years ago and is expected to reject the result if he loses again – potentially pitching the United States into chaos.

For Republican A.D. Jefferson, a 62-year-old laborer attending Harris’s rally in Houston, the Trump turmoil is too much.

“I just think she’s less controversial,” he told AFP. “I’m a Republican, but I feel like Trump is just too chaotic for me.”

- Beyonce, then Michelle -

Fresh off a high-energy rally in Texas with pop icon Beyonce to highlight Republican restrictions on abortion, Harris heads to Kalamazoo, Michigan where she will court voters by deploying one of the Democratic Party’s most popular emissaries: former first lady Michelle Obama.

Her husband Barack Obama joined Harris on Thursday for a rally in Georgia.

Harris, 60, campaigns Sunday in Philadelphia, Pennsylvania, the largest city in the largest of the swing states likely to determine the outcome of the presidential election under the US electoral college system.

She will go from neighborhood to neighborhood across the city persuading residents to cast their ballot, as she targets historically Black and Latino districts.

Trump, who swept the three Blue Wall states in his shock victory in 2016 only to see Joe Biden reclaim them for Democrats four years later, is strategizing that clawing back one or more of the trio and winning the other so-called Sun Belt swing states would propel him back into the White House.

With just a few thousands votes possibly the difference between victory and defeat in the tightest of swing states, Trump holds rallies Saturday in Michigan and Pennsylvania, where a robust ground game and relentless barnstorming of the battlegrounds could prove decisive.

They follow the release late Friday of the extended, three-hour interview that Trump taped for the Joe Rogan Experience, America’s most popular podcast.

He is seeking to woo Rogan’s massive, largely male audience, as the Republican candidate hunts for viral moments that tap into his everyman appeal.

- The Trump show -

Then on Sunday night, Trump performs a campaign quirk: rallying his supporters in Madison Square Garden, the iconic arena in the heart of Democrat-heavy New York.

Analysts have pondered why Trump is campaigning in his native New York despite virtually no chance of flipping the state.

The brash billionaire and onetime reality television star may be keen to orchestrate a spectacle and demonstrate he can fill an arena in a Democratic bastion.

But critics, including Trump’s 2016 rival Hillary Clinton, have noted that Madison Square Garden was also the scene of a 1939 pro-Nazi rally organized by a group supportive of Adolf Hitler.

“She said it’s just like the 1930s,” Trump said at a Friday rally in Michigan, referring to Clinton’s remarks a day earlier on CNN. “No it’s not, no. This is called ‘Make America Great Again.’”

The weekend campaigning follows a heated row over accusations that the Republican ex-president has been running to be an authoritarian leader, following claims by Trump’s longest-serving White House chief of staff, echoed by Harris, that Trump is a “fascist” who cannot be trusted with power again.