Hillary Clinton celebrates greets the crowd after winning the New York state primary election on April 19. | AP Photo Clinton camp: Sanders is all but done The Democratic front-runner's aides say that Sanders' time has run out.

Hillary Clinton's top strategist on Wednesday suggested that Bernie Sanders' path to the Democratic nomination is virtually non-existent and will continue to shrink as the Democratic front-runner picks up delegates in the weeks to come.

Remarking that Sanders faces a "pretty daunting" deficit after the campaign's "resounding victory" in the New York primary, chief Clinton pollster and strategist Joel Benenson said the former secretary of state's lead grew "even more insurmountable."


Benenson also rejected the notion that Sanders has any path to catch Clinton, noting that the campaign has continued to add to its pledged delegate lead, "and the real estate is disappearing beneath his feet."

"Next Tuesday, these races are going to be closely contested, but more than 400 delegates come off the table," he continued. "He just doesn’t have enough left to make a credible case that he can do what he’s gotta do to get within striking distance of us even.”

The latest declaration comes as the race continues to take on a more vigorous, contentious and increasingly personal tone. In an interview with POLITICO's Glenn Thrush, a senior Clinton aide remarked of the rival campaign, "We kicked his ass tonight... I hope this convinces Bernie to tone it down. If not, f--- him.”

But the Sanders campaign showed no sign of backing down Wednesday.

"We still have a path to the nomination, and our plan is to win the pledged delegates in this primary," Sanders wrote in a fundraising email to supporters soliciting a $2.70 donation. "Next week five states vote, and there are A LOT of delegates up for grabs. I am going to keep fighting for every vote, for every delegate, because each is a statement of support for the values we share.

As that email hit inboxes, senior Sanders adviser Tad Devine appeared on CNN to extol his candidate's "very powerful message" on the economy going forward into states like California, which votes June 7.

“We lost more than we thought we would yesterday. We thought the race would be a little bit closer, we’d pick up some more delegates," Devine conceded. "But we can still do it."

Pointing to exit polls in New York that suggested voters saw Clinton running the more unfair campaign, Devine also noted that more people also said their campaign was energizing the Democratic Party.

“I think Bernie Sanders’ case was heard in New York. She succeeded in her home state, but I think more voters will respond to it all across this country, all the way through California and the District of Columbia [which holds its Democratic primary June 14],” Devine said.

Responding to a question about Sanders’ poor performance with African-American voters in New York, Devine again admitted that the campaign had to do better to win in a general election but noted that the Clintons have a “strong footprint there, and we congratulate them.”

“Yeah, but Tad, it’s like the end of April at this point," CNN's Kate Bolduan remarked. "I mean, what more reintroduction do you have time for?”

“Well, I think we have a lot of time. We’ve got over 1,400 delegates still to be picked. We’ve got huge states like California still and I think we’ll be able to demonstrate by the time we get to the end of this process that Bernie Sanders’ appeal is across the broad spectrum of the party," he said, adding that only Sanders can bring in young people and independents in a general election.

After next Tuesday's contests in Connecticut, Delaware, Maryland, Rhode Island and Pennsylvania, Benenson said Sanders will have to win 60 percent of the remaining delegates. Sanders "will do really well" in those states, Devine remarked.

"He’s going to win not just states, he’s going to have to win massive landslides," Benenson claimed. "He’s only done that in two states, where he’s gotten 57 or 58 percent of the delegates: Vermont and New Hampshire. That happened months ago. All these states he’s been winning and adding on, he hasn’t been piling up net delegates at the 58-42 range that he would need. It’s just not doable for him. He can point to all the states on the map that he wants to, but he has no evidence."

After Clinton trounced Sanders in New York, she leads the Vermont senator 1,428 to 1,151 in pledged delegates. Adding in superdelegates, the former secretary of state's lead blows out to 1,930 to 1,189 in the race to the 2,383 needed the clinch the nomination.

On Tuesday evening, Sanders campaign manager Jeff Weaver appeared on MSNBC to state his candidate's case going forward, arguing that superdelegates would turn around once they saw Sanders as a more electable candidate against Donald Trump or Ted Cruz.

Pointing to a map of states still to cast their ballots, Weaver predicted that Sanders would perform well and win states and delegates throughout the remaining primaries.

"Look, we're going to go to the convention. It is extremely unlikely that either candidate will have the requisite number of pledged delegates to get to this number, right?" Weaver said. "So it's going to be an election determined by the superdelegates."

Benenson was having none of it, noting that Sanders trails Clinton by more than 2.5 million votes in the popular primary vote.

"Why would pledged delegates, which Sen. Sanders has been highly critical of, not just for their role in the process, but branding them as part of the establishment—why would they listen to that argument from him? It just has no water," Benenson said. "If you can’t win in the Democratic primary with a diverse coalition like Hillary Clinton’s built, you’re not going to win in swing states that she’s won like North Carolina, like Florida, like Ohio. He has no evidence of winning in those states consistently. It’s just not an argument that savvy political people are gonna buy.”

Clinton campaign manager Robby Mook took another shot at the argument later on MSNBC, remarking, "That would be a pretty big migration of super delegates considering how big Hillary’s lead is with pledged delegates. We’re curious why Sen. Sanders would want to override the popular vote."

Despite those strong words, Benenson declined to tell Sanders that he should get out of the race, noting that the Vermont senator and his team returned home Wednesday. Clinton press secretary Brian Fallon sounded a similar line in an earlier CNN segment.

“He’s got decisions to make that we’ll let him make," Benenson added. "I have no idea what the nature of those conversations are. We’ll see what comes out of that. We’re going on to Connecticut and Maryland and Pennsylvania, because we believe we’re gonna add to our net delegate lead again on next Tuesday, April 26, and the real estate just is going to be gone from under his feet.”

Brianna Ehley contributed to this report.