How Sanders remaining in race is costing taxpayers

What about Bernie?

Sanders was mathematically eliminated from the Democratic presidential race earlier this month, but the Vermont senator isn't ready to bow out and that means highly trained Secret Service agents shadow his every move at a cost to taxpayers of tens of thousands of dollars a day.

Sanders, who touts his frugality and espouses cost-saving national policies, has laid off much of his staff and is no longer holding campaign events or rallies. Yet every day a detail of Secret Service agents protects a man who won't be president. As many as 50 agents are involved in protecting each candidate on a daily basis.

The Secret Service won't say what the agency is spending to protect Sanders. But former Secret Service Director Mark Sullivan testified in April 2008 that the agency was spending about $37,000 to $38,000 a day to protect presidential candidates, including then-Sen. Barack Obama. Sullivan told a budget panel at the time that the agency expected that cost to be about $44,000 a day as the campaign "tempo" picked up.

Though a specific cost is hard to pin down, it's fair to say that Sanders' protective detail costs U.S. taxpayers tens of thousands of dollars a day.

Since 1968, major presidential candidates have been afforded a protective detail starting about 120 days before the election. But candidates can and have asked for protection well in advance of the nominating conventions.

Sanders' request for protection was approved by Homeland Security Secretary Jeh Johnson earlier this year and suit-clad agents started surrounding him in February. At the time, he met the requirements for a protective detail in advance of his party's convention in part because he was a candidate in a major party who had "some degree of prominence as shown by opinion polls" and was campaigning for primaries in at least 10 states.

But primary season is over and Sanders doesn't have enough delegates to overtake Hillary Clinton for the nomination.

So when will the Secret Service stand down? That's unclear.

Sanders can call for the security force to leave his side any time he wants or formally drop out of the race. But short of that or a directive from Johnson, the armed security detail likely will surround him until Clinton is formally nominated, said Secret Service spokeswoman Catherine Milhoan.

Sanders has said very little about his future plans, other than he will work to keep Trump out of the White House.

Sanders' Senate colleagues said it was up to him to decide when and how to get out of the race.

"You know, that's his decision," said Sen. Richard Blumenthal, D-Conn.

Sen. Edward Markey, D-Mass., said said there was no need for Sanders to drop out of the race now.

"I think that Bernie still has an opportunity to play an extremely constructive role at the (Democratic) convention to ensure that Donald Trump never becomes president," Markey said. "I think it's still within the realm of possibilities that that's exactly how it's all going to play out."