Sanders warns Clinton to pick a true progressive running mate

Washington: Bernie Sanders cautioned Democratic rival Hillary Clinton in an interview aired Sunday that she will lose the backing of his many supporters unless she picks a hardline progressive as her running mate.

"That means having a candidate who can excite working families, excite young people, bring them into the political process, create a large voter turnout," the Vermont senator said on NBC's "Meet the Press."

Clinton's lead in the race for the Democratic presidential nomination is nearly insurmountable, but Sanders has continued to win primaries and draws far larger and more raucous crowds to his rallies.

The 74-year-old senator has mobilized large numbers of young voters and self-identified independents -- areas where Clinton hopes to make inroads before the November election.

Sanders was asked on NBC about one man seen as a possible No. 2 to Clinton: Senator Tim Kaine of Virginia, a former governor of that state who was also considered a possible Obama running mate in 2008.

"I really like him very much," Sanders said, but he declined further comment.

Kaine is considered a centrist Democrat, who emphasizes the need to work with Republicans to get things done.

"Virginians want you to work across the aisle," he told The Washington Post in 2014, while adding that the best politics is "to be affirmatively proud of who you are and what you are, and then work together."