Even hours later, few people could agree on what, exactly, former President Donald J. Trump said about Milwaukee when he met with House Republicans in Washington on Thursday.

But on a day when Mr. Trump returned to Capitol Hill to unite congressional Republicans behind him, more than three years after a group of his supporters mounted a violent effort to try to keep him in the White House, much of the focus was instead on stray comments he made, including about a populous city in a critical battleground state that will soon play host to his nominating convention.

According to various people in the room, Mr. Trump, during his meeting with House members at the Capitol Hill Club, complained that the pop music megastar Taylor Swift would support President Biden over him. Mr. Trump has previously argued that Ms. Swift, who endorsed Mr. Biden in 2020 but has not done so this year, should back him instead.

He falsely claimed that former Speaker Nancy Pelosi’s daughter once told him that he and her mother might have been a good match, a comment that some lawmakers interpreted to refer to a romance, while others said that it merely referred to a professional partnership. One of Ms. Pelosi’s daughters pushed back on social media, calling Mr. Trump’s reported remark a lie.

And perhaps most striking, he disparaged the city of Milwaukee — the most populous city in the swing state of Wisconsin and the site of the Republican National Convention in July — over its crime rate, remarks that lent themselves to some dispute.

Mr. Trump’s exact phrasing and his degree of disdain for the city were disputed by his allies, including some in the room. But his campaign spokesman, Steven Cheung, acknowledged on X that Mr. Trump had criticized the city’s crime rate and its role in his loss in the 2020 election, which Mr. Trump still insists he won.