WASHINGTON • With former US vice-president Joe Biden now holding an all-but-insurmountable lead over Senator Bernie Sanders in the United States presidential primary contest, many Democrats have shifted their attention to a favourite quadrennial parlour 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 running mate. That has opened the path for Democratic officials to start picking favourites - from a socially safe distance.

In discussions with The New York Times since Mr Biden's big primary victories on Tuesday, 60 Democratic National Committee (DNC) 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 Ms Stacey Abrams, a former state House leader whose defeat in the 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 Governors 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 criticising Ms Harris' 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 or Ms Sally Yates, the former assistant attorney-general whom President Donald Trump fired three years ago.

A female vice-president would be historic: Only two women - Representative Geraldine Ferraro of New York in 1984 and Governor Sarah Palin of Alaska in 2008 - have been nominated, and none has ever served in the White House.

That barrier-breaking appeal could give Mr Biden's candidacy a shot of energy, an acknowledgement of the role women have played in boosting the party during the Trump era.

Prominent Democratic activists and leaders have been vocal with their desires that the ticket should include a woman, after the last major female contender, Ms Warren, 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 Ms Christine Pelosi, a DNC member from San Francisco and 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.

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.

His choice of running mate 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 Mr John Podesta - who, as Mrs 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."

NYTIMES