 -- It’s not just the Republicans who may be headed to a contested convention. Bernie Sanders' campaign manager believes the Democrats may be going in the same direction.

Sanders campaign manager Jeff Weaver says that if Hillary Clinton fails to reach a majority with pledged delegates ahead of the Democratic convention, Sanders will “100 percent, absolutely” challenge her for the nomination –- even if Clinton has more votes than Sanders.

“The way the math is right now, it is very, very, very unlikely that either candidate will arrive at the convention with enough pledged delegates to win the nomination,” Weaver said in an interview on ABC News’ “Powerhouse Politics” podcast.

While the majority of superdelegates are expected to vote for Clinton, Weaver noted that “those people are not pledged when they get there” and believes that they will “take a second look” at Sanders because “these people want to win … in November.”

Clinton would need to win 63 percent of the 1,741 remaining pledged delegates up for grabs to clinch the nomination counting only pledged delegates before the convention, while Sanders would need to win 78 percent.

Clinton currently has 1,280 pledged delegates while Sanders 1,030. Each candidate would need 2,383 delegates to clinch.

Weaver pointed to the strength Sanders has shown among independent voters who have participated in the Democratic primary and Clinton’s relative weakness by comparison, as something that should make superdelegates “nervous” about the Democratic frontrunner.

“There is very, very, very little enthusiasm for Secretary Clinton,” he said. “So you can imagine if we’re looking at a pool of independent voters beyond leaning voters…that her standing would be even less and that should be cause for people to be nervous.”

Weaver defended Sanders for calling Clinton “unqualified” to be president on Wednesday, arguing that the unqualified line of attack originated in the Clinton campaign.

“This was an attack that was launched on their side,” Weaver said, pointing to reports that the Clinton campaign was embarking on a strategy to “disqualify” Sanders, even though Clinton has never explicitly said that Sanders is “unqualified” to be president.

“I went to law school too, I know how to say things without saying them,” Weaver said of Clinton. “Clearly that was the attack…everyone understands what was going on there.”

And with the New York primary next on the calendar, Weaver made reference to the Vermont senator’s New York roots -- saying he is prepared to “campaign like a Brooklynite” -- as the rhetoric between the campaigns heats up.

“What we want to do is continue to have an issue oriented campaign but if the Clinton campaign, the secretary, want to have sharper elbows, that’s fine, Bernie Sanders will campaign like Brooklynite,” he said.

On the topic of Sanders’ recent interview with the New York Daily News Editorial Board, in which he struggled to explain some of the specifics of how he would break up big banks, which has been a hallmark promise of his campaign, Weaver pointed to editorials that have since been published suggesting it was the New York Daily News that was confused about the government’s financial regulatory powers, not Sanders.

“The problem was that the questioners were confused about the various regulatory branches of government and so it made for a very confusing interview,” he said.

Asked about how Sanders message to break up big banks plays in the Empire State, where the country’s financial industry is headquartered, Weaver explained that the campaign’s message won’t do away with banking jobs, and could in fact do the opposite – by creating more small banks.

“What we are talking about is breaking up the big banks so that there are in fact more banks, not fewer banks, so those jobs will all still be in New York, but it’s a question of breaking up the economic and political power of these giant mega Wall Street firms,” he said.