Tim Walz touts record and attacks Trump in first rally as VP pick

At Tuesday night’s rally in the key swing state of Pennsylvania, Ms Harris, currently the US vice-president, said she and Mr Walz were the “underdogs” in what is expected to be a close election, but had the momentum.

Ms Harris, who announced her choice of Mr Walz earlier in the day, introduced her running mate as “a fighter for the middle class, a patriot”.

Mr Walz told a packed arena in Philadelphia that Trump “sees the world differently”.

“He doesn’t know the first thing about service – because he’s too busy serving himself,” said the former army sergeant and football coach.

To cheers from the raucous crowd, he also invoked a viral attack line that caught the eye of the Harris campaign as she considered who would be her running mate.

“These guys are creepy and, yes, just weird as hell,” Mr Walz said of their Republican challengers.

The governor also said he “can’t wait to debate” Republican vice-presidential nominee JD Vance, “that is, if he’s willing to get off the couch and show up,” Mr Walz added.

He also showed the plain-spoken, folksy style that has won praise from Democrats, as he took a jab at Republicans on abortion access.

“Mind your own damn business!” he said, drawing an ovation from the crowd of more than 10,000 at Temple University.

Ms Harris and Mr Walz have just launched a five-day tour of key battleground states.

They will also speak at the Democratic National Convention, which runs from 19 to 22 August in Chicago.