Former President Obama is planning to hit key swing states to boost Vice President Kamala Harris’ campaign for the White House, starting Thursday in Pittsburgh.

The Harris campaign says Obama will travel around the country over the final 27 days ahead of the election. The former president and Harris have a friendship that goes back more than 20 years, from when they first met while he was running for a Senate seat from Illinois.

Obama — along with other key Democrats — was a part of the behind-the-scenes push to persuade President Biden to step away from the 2024 race. Obama’s presence on the campaign trail will be a contrast to the relatively few stops made by Biden since he made way for Harris.

In Obama’s speech at the Democratic convention in August, he said Harris “wasn’t born into privilege. She had to work for what she’s got.”

“And she actually cares about what other people are going through,” the former president said.

Harris was an early supporter of Obama’s 2008 presidential bid, and knocked on doors for him in Iowa ahead of its caucus that led off voting in the Democratic primary.

Weissert writes for the Associated Press.