Democratic presidential front-runner Hillary Clinton’s advisers and allies have begun extensive discussions about who should be her running mate, seeking to compile a list of 15 to 20 potential picks for her team to start vetting by late spring, according to The New York Times.

Clinton’s team will grapple with complicated questions like whether the United States is ready for an all-female ticket, and whether her choice for vice president would be able to handle working in a White House in which former President Bill Clinton wielded significant influence on policy.

Campaign advisers and more than a dozen Democrats close to the campaign or the Clintons say the candidate does not have a front-runner in mind.

Among the names under discussion: Sens. Tim Kaine and Mark Warner, former governors from the key state of Virginia; Ohio Sen. Sherrod Brown, who represents both a more liberal wing of the party and a swing state; former Massachusetts Gov. Deval Patrick, a prominent African-American Democrat; and Thomas E. Perez, President Obama’s Labor secretary and a Hispanic civil rights lawyer.

But Mrs. Clinton is also open to a woman, campaign advisers said. One obvious possibility is Massachusetts Sen. Elizabeth Warren, hugely popular among progressive Democrats, though she has not been helpful to Clinton’s campaign, declining to endorse the former secretary of state.

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