WASHINGTON — Senator Amy Klobuchar of Minnesota announced late Thursday that she was withdrawing from consideration to be the running mate to former Vice President Joseph R. Biden Jr. on the Democratic ticket.
Ms. Klobuchar, who mounted her own campaign for the presidency before dropping out and becoming one of Mr. Biden’s most spirited surrogates, said during an MSNBC interview that she called Mr. Biden on Wednesday night and told him he should choose a woman of color to be his running mate.
Ms. Klobuchar, a moderate and veteran of the Senate like Mr. Biden, was known to have a strong rapport with the presumptive Democratic nominee, and was an early favorite of a significant number of his donors and supporters. But her case for being Mr. Biden’s running mate was badly damaged after the Memorial Day killing of George Floyd in the custody of Minneapolis police officers. The death, which has prompted weeks of demonstrations and protests against police violence across the country, led to renewed scrutiny of Ms. Klobuchar’s career as a local prosecutor in Minneapolis.
“After what I’ve seen in my state and what I’ve seen across the country, this is a historic moment and America must seize on this moment,” she said. “I truly believe, as I told the vice president last night, that I believe that this is a moment to put a woman of color on that ticket.”
In a Twitter post late Thursday, Mr. Biden praised Ms. Klobuchar and described her as a key ally in the contest to beat President Trump in November.
Senator Kamala Harris of California, who also ran against Mr. Biden and is the only black woman in the Senate, is widely regarded as a strong candidate for the vice-presidential slot. Several other black women are being vetted by Mr. Biden’s search committee, including two whose prospects have risen as the national debate over racial justice amplifies calls for him to select a woman of color: Representative Val Demings of Florida and Mayor Keisha Lance Bottoms of Atlanta. Mr. Biden is also considering Susan E. Rice, the former national security adviser under President Barack Obama, the people familiar with the process have said.
Ms. Klobuchar was still being vetted until her Wednesday night phone call to Mr. Biden, according to a person familiar with Mr. Biden’s running mate selection process. But in conversations earlier this week, Ms. Klobuchar suggested to friends that she recognized that her own history made it difficult for Mr. Biden to select her, given the widespread Black Lives Matter protests.
As the district attorney in Hennepin County, which encompasses Minneapolis, Ms. Klobuchar developed a tough-on-crime reputation 20 years ago that is a difficult fit with modern Democratic Party politics. Though she has rebutted criticism that she failed to prosecute police misconduct, her record was scrutinized during the presidential campaign and would quite likely have become a major headache for Mr. Biden’s campaign had he selected her as the running mate.
One person she spoke with on Monday said Ms. Klobuchar relayed then that she understood she would not be selected, and said she cited the scrutiny of her record as prosecutor. A Klobuchar spokeswoman disputed the recollection of the call.
Ms. Klobuchar’s declaration that Mr. Biden should choose a woman of color created something of an awkward political dynamic for Senator Elizabeth Warren of Massachusetts, another former presidential rival who is being considered by Mr. Biden as a possible running mate. Ms. Warren is the most prominent and formidable white candidate in the running, and she is far along in the vetting process.
Other white candidates under consideration include Senator Tammy Baldwin of Wisconsin, Gov. Gretchen Whitmer of Michigan and Gov. Gina Raimondo of Rhode Island.
Asked by the MSNBC host Lawrence O’Donnell if her past record as a prosecutor would have made it difficult for her to “function” as Mr. Biden’s running mate, Ms. Klobuchar said it was not a factor in her decision.
“I think I could have functioned fine,” she said. “There’s a lot of untruths out there about my record and now is not the time to debate them.”