WASHINGTON — With former Vice President Joseph R. Biden Jr. now holding an all but insurmountable lead over Senator Bernie Sanders in the presidential primary contest, many Democrats have shifted their attention to a favorite quadrennial parlor game: the vice-presidential search.
Mr. Biden has shown his hand in a big and unusual way for a front-runner, saying he would pick a woman as a running mate. That has opened the path for Democratic officials to start picking favorites — from a socially safe distance.
In discussions with The Times since Mr. Biden’s big primary victories on Tuesday, 60 Democratic National Committee members and congressional and party leaders most frequently proposed three former rivals of Mr. Biden as his running mate — Senator Kamala Harris of California, Senator Elizabeth Warren of Massachusetts and Senator Amy Klobuchar of Minnesota. Next up was Stacey Abrams, a former state House leader whose defeat in 2018 Georgia governor’s race remains disputed by many in the party.
Other popular suggestions included Senator Catherine Cortez Masto of Nevada and Representative Val Demings of Florida. The Democrats interviewed also proposed seven other women, including Govs. Gretchen Whitmer of Michigan and Michelle Lujan Grisham of New Mexico.
While de facto presidential nominees typically keep their list of potential running mates closely held, Mr. Biden has helped fuel speculation by eagerly rattling off names for months — nearly all of them women. Even his wife, Jill, offered her take in a private fund-raiser earlier this month, praising Ms. Klobuchar and criticizing Ms. Harris’s debate stage attack on her husband last summer.
Mr. Biden, at various points, has suggested he might choose Ms. Abrams, Ms. Klobuchar, Senators Jeanne Shaheen and Maggie Hassan of New Hampshire or Sally Q. Yates, the former assistant attorney general whom President Trump fired three years ago.
A female vice president would be historic: Only two women — Representative Geraldine Ferraro of New York in 1984 and Gov. Sarah Palin of Alaska in 2008 — have been nominated, and none have ever served in the White House. That barrier-breaking appeal could give Mr. Biden’s candidacy a shot of energy, an acknowledgment of the role women have played in boosting the party during the Trump era.
Prominent Democratic activists, officials and leaders have been vocal with their desires that the ticket include a woman, after the demise of the last major female candidate, Ms. Warren, who ended her campaign two weeks ago.
“I’ve been predicting a woman on the ticket since 2017 and demanding it since Warren dropped out,” said Christine Pelosi, a D.N.C. member from San Francisco who is the daughter of House Speaker Nancy Pelosi. “It’s really important to have the ability to lead America in the depression we will enter if we don’t flatten the curve and find a cure. The best pick is the woman Joe or Bernie trusts the most to be president and commander-in-chief.”
Some of the party’s most liberal members and supporters of Mr. Sanders suggested that choosing Ms. Warren, a fellow liberal, would help Mr. Biden appeal to the progressive and young voters who have backed the Vermont senator in the primary. Choosing a moderate like Ms. Klobuchar, they say, would dampen general election enthusiasm.
“Whoever ends up the nominee should pick Senator Warren,” said Tefere Gebre, a D.N.C. member from Maryland who is executive vice president of the AFL-CIO. “I would be less enthusiastic if it’s the senator from Minnesota.”
Yet, with the coronavirus upending every part of American society, including the presidential campaign, Mr. Biden may be forced to deviate from the standard playbook.
Mr. Biden’s running mate pick will be viewed through the lens of a public health and economic crisis, perhaps raising the stock of candidates who have more experience, or pushing him to consider someone from outside of government.
“You could imagine some highly successful person from a different walk of life being considered, and that could expand the list a lot,” said John Podesta, who as Hillary Clinton’s campaign chairman was involved in her vice-presidential search. “A college president or a medical professional, somebody who would send a pretty powerful signal that what you care about is strength, performance, a commitment to facts and sound decision-making.”
Mr. Biden’s campaign said it was beginning to build a team to conduct a “vigorous vetting process.” Some close to the campaign say the team is in the early stages of compiling a list of potential running mates and then will vet them. Beyond his own experience as Barack Obama’s vice president, Mr. Biden has a deep bench of aides to consult. One of his closest advisers, Ron Klain, helped do vice-presidential vetting for Al Gore in 2000.
Mitt Romney cut his campaign’s list of about 80 potential running mates to 20 in early April 2012. By late July, the list had been narrowed to five men, after the one woman under serious consideration, former Secretary of State Condoleezza Rice, declined the campaign’s invitation to be vetted. (Mr. Romney eventually chose Representative Paul Ryan.)
Donald Trump’s 2016 vetting process was less streamlined, but among those he interviewed during his search was Senator Joni Ernst of Iowa.
Mrs. Clinton started with a list of 40 possible candidates, which was narrowed to nine who underwent a process of serious vetting, an interview and a campaign appearance with the candidate. While she considered a number of women to be vice president, only Ms. Warren advanced to the final stages of the process.
For Mr. Biden, 77, a much younger woman could assuage concerns about his age and critiques about a primary process that started with the most diverse field in history and ended with two white men.
Mr. Biden’s campaign hopes the early announcement that he would select a woman will give his operation a shot of enthusiasm from voters, even as the presidential election heads into a deep freeze because of the coronavirus. On Thursday, his campaign sent a fund-raising appeal asking supporters to “commit to standing with” Mr. Biden and his future female running mate.
By announcing he will pick a woman, Mr. Biden is aiming to give his ticket a modern-day balance in a party focused on issues of racial and gender representation. Past nominees have chosen running mates who provided geographic diversity (Lloyd Bentsen in 1988) or offered the promise of winning a key state (Mr. Ryan, from Wisconsin, in 2012). Mr. Obama, just four years into his Senate term, chose Mr. Biden in 2008 to ease concerns about his own relative lack of experience and help appeal to white working-class voters.
Choosing Ms. Harris, 55, would not only provide not a gender balance but also would add a black woman to the ticket after black voters helped revive Mr. Biden’s campaign in February. But as Jill Biden’s recent criticism indicated, the memory of Ms. Harris’s debate stage attack may hinder her chances.
“I have to tell you that I’m a little torn in terms of my choices,” said Alma Gonzalez, a D.N.C. member from Florida. “If it were me and if I was Joe Biden, I would say to Senator Harris, ‘Do you want to be on the Supreme Court or be my vice president?’”
Presidential candidates rarely place public restrictions on their pick, preferring to keep options open so they can pivot their selection to suit the shifting dynamics of the campaign. Veterans of past vice-presidential searches said the most important elements have been how comfortable the nominees are with their would-be partners.
And while past campaigns spent months vetting candidates and agonizing over running-mate strategy, there’s very little academic research suggesting that the vice-presidential pick has a huge impact on winning the general election.
“The first and most important criteria is, can this person help you win in November and will they at least not hurt you in November,” said Mr. Podesta.
For Mrs. Clinton, that meant ruling out candidates from states with Republican governors, like Senator Sherrod Brown of Ohio. If she won, her team feared that Mr. Brown could be replaced in the Senate by a Republican and shift the balance of the chamber away from her future administration.
Unlike any nominee since Mr. Gore, Mr. Biden has a unique view into the selection process, having gone through it himself. While Mr. Obama started with a list of 20 candidates, he faced pressure to select Mrs. Clinton as his running mate and create a “unity ticket.” After Mr. Obama rejected that idea, the choice came down to a “coin toss” between Mr. Biden and Senator Evan Bayh of Indiana. Mr. Biden was more energetic and enthusiastic in his interview, according to aides.
In an interview earlier this month, Mr. Biden cited his close relationship with Mr. Obama as a model for his selection process, saying the president was able to trust him with key pieces of his agenda.
“For me, the most important thing in choosing a vice president is whether or not the person is simpatico with me in terms of where I want to take the country,” he said. “It’s really important that the next president is able to do what Barack was able to do with me.”