US President Donald Trump and his Democratic rival Joe Biden launched a final campaign sprint on Saturday ahead of the November 3 presidential election.

With more than 91 million votes already cast, Trump and Biden are out of time to reshape the race.

They are instead focusing on their base and making sure that any potential supporters have either already voted or plan to do so in person.

Biden held his first in-person campaign events with former president Barack Obama on Saturday in the predominantly Black cities of Detroit and Flint, Michigan.

Obama will campaign for Biden on Monday in Georgia and in South Florida, another area of potential concern if Latino voters sit out the election.

On Saturday, Obama said Trump was a president “who goes out of his way to insult people just because they don’t support them”.

“With Joe and Kamala at the helm,” he said, “you’re not going to have to think about them every day. You’re not going to have to argue with your family about him every day.”

Biden planned to spend much of Sunday in Philadelphia, which is 30 miles from his longtime home in Wilmington, Delaware.

Biden established his campaign headquarters in Philadelphia.

The city gets intense focus because it’s such a deep trove of Democratic votes, especially nonwhite voters.

On Sunday, Trump continued his final campaign sprint in Michigan, where he will speak at 10 rallies in seven swing states.

Trump is down in the latest polls and is turning to these large gatherings to help keep his message in front of voters.

“This is a hell of a day. You guys must love Trump, this place is packed,” said Trump, who jokingly complained throughout his speech about the cold.

“It’s really a contest to see if we can all stand it. And we’ll get through it. And we’ll love it.”