Donald J. Trump often cites his undergraduate degree from University of Pennsylvania’s prestigious Wharton business school as evidence that he is a pretty smart guy and singularly qualified to be president.

But some in the Wharton community would prefer the presumptive Republican presidential nominee simply leave his alma mater out of his campaign.

In an open letter to Mr. Trump, Wharton backers wrote that they have been “deeply disappointed” in his candidacy and “outraged that an affiliation with our school is being used to legitimize prejudice and intolerance.”

“Although we do not aim to make any political endorsements with this letter, we do express our unequivocal stance against the xenophobia, sexism, racism, and other forms of bigotry that you have actively and implicitly endorsed in your campaign,” said the letter, which was posted to Medium.com and as of Monday morning carried the signatures of about 2,000 Wharton students, alumni, faculty members and other supporters.