Bernie Sanders began laying off staff today as his campaign came to grips with its losses yesterday in four states.

The Democratic presidential candidate's campaign told staffers working on those contests to begin looking for new jobs rather than relocate to states with upcoming primaries as they have in the past, Politico reports.

It's one sign in a series since yesterday that Sanders' campaign is flat-lining.

Sanders spokesman Michael Briggs said the move was about 'right-sizing' the campaign now that 80 percent of the primary calendar is complete.

He side-stepped Politico's suggestion that the decision to cut staff is coming from a point of weakness and said it's 'coming from a posture of reality.'

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Bernie Sanders began laying off staff today as his campaign came to grips with its losses yesterday in four states

Bernie Sanders continued on to Indiana, speaking at Purdue University in West Lafayette today, but his path to the nomination has become very, very narrow

Last night, Bernie Sanders moved on to West Virginia, where voters wouldn't be heading to the polls for another two weeks while getting trounced in Pennsylvania, Maryland, Delaware and Connecticut

The senior Sanders aide confirmed the layoffs in a statement afterward from Indiana, where Sanders is rallying his supporters today.

'Our campaign has now completed 80 percent of the primaries and caucuses. We look forward to winning here in Indiana next Tuesday and in the few remaining states and territories holding primaries and caucuses in May and June,' Briggs said.

Cutting to the chase, he said, 'That means that we no longer require many of the loyal and dedicated state and national support staffers who helped us in places like New York, Connecticut, Rhode Island, Maryland, Delaware, Pennsylvania and other states where the nominating contests have been completed.'

Briggs said the campaign still has more than 300 workers. He did not include a state-by-state breakdown or say how many of those workers are full-time field staff.

The statement concluded with the assertion that the campaign 'believes that we have a path toward victory and we're going to marshal our resources to do everything we can to win the Democratic nomination.'

Sanders lost Connecticut, Pennsylvania, Delaware and Maryland to Clinton last night, boosting her lead over him up to nearly 330 pledged delegates. The sole state that the senator surpassed her in votes was Rhode Island.

Now, just 14 contests remain. New Jersey and California are the only ones with pledged delegate counts large enough for Sanders to catch up.

Both states vote in more than a month on June 7.

Indiana is next in the line up, and its voters go to the polls on Tuesday.

Sanders rededicated himself to the task at hand during a speech there today where he promised his supporters that he is 'in this campaign to win and become the Democratic nominee.'

At the West Lafayette event he acknowledged that it will be a struggle but said it's not out of the realm of possibility.

'We are behind today. But you know what? Unusual things happen in politics,' he said. 'With your help, superdelegates may reach the conclusion that Bernie Sanders will be the strongest candidate against Donald Trump or any other candidate.'

The layoffs indicate that his campaign has concluded that he will not be the Democratic nominee, however, and no longer needs a massive national staff.

'We are behind today. But you know what? Unusual things happen in politics,' Bernie Sanders told a crowd at Purdue University today, vowing to press on while news of staff layoffs trickled out

There are 14 primary contests left, wrapping up with Washington, D.C.'s Democratic primary on June 14, though Bernie Sanders has said he would take his campaign all the way to the convention

Clinton is expanding rather than contracting. Her campaign opened a second floor at its headquarters this month as it gears up for the general election.

Sanders sent mixed messages about the purpose of his continued candidacy yesterday evening as his campaign reassessed its prospects following the stinging defeats.

He told fans of his in West Virginia that he could win the state if there's a large enough turnout after giving a new speech that mostly avoided references to Clinton and seemed to set the stage for a battle over the Democratic Party's platform at the convention more than anything else.

Sanders sent out a statement later in the evening congratulating Clinton on her success in the day's primaries that committed to 'issue-oriented campaigns' in upcoming states.

'The people in every state in this country should have the right to determine who they want as president and what the agenda of the Democratic Party should be. That's why we are in this race until the last vote is cast,' he said.

Foreshadowing the brewing fight over the direction of the party, he also said, 'That is why this campaign is going to the Democratic National Convention in Philadelphia with as many delegates as possible to fight for a progressive party platform.'