Mediaboss Marketing

Watch CNN and NY1's Democratic debate, moderated by Wolf Blitzer, Thursday, April 14 at 9 p.m. ET.

"They're going to question my qualifications, well I'm going to question theirs," Sanders said Thursday during a news conference in Philadelphia.

"The Washington Post had a headline that said 'Clinton questions whether Sanders is qualified to be president.' That was what was thrown at me."

"I believe the Clinton campaign told CNN that their strategy is, 'we go into New York and Pennsylvania. Disqualify him, defeat him and unify the party later,' "he said.

Clinton herself has never said Sanders isn't qualified to be president. When asked Wednesday on MSNBC if she thought Sanders was "ready to be president," she said: "I think he hadn't done his homework and he'd been talking for more than a year about doing things that he obviously hadn't really studied or understood, and that does raise a lot of questions."

By Thursday morning, Clinton laughed off questions about Sanders' assertion that she isn't "qualified" for the presidency.

"It's kind of a silly thing to say," she told reporters in New York. "But I'm going to trust the voters of New York who know me and have voted for me three times."

At his news conference, Sanders said he was trying to run an "issue-oriented campaign" and blamed "the media" for taking things off course.

He then repeated on Thursday the same swipes on Clinton he cited the night before.

"My response is if you want to question my qualifications, then maybe the American people might wonder about your qualifications Madame Secretary," he said.

Sanders' remarks rankled Clinton's aides, with many arguing it shows Sanders' campaign growing desperate in the face of growing odds to win the Democratic nomination. Clinton's aides were outraged late on Wednesday night, when they gathered for a conference call about the change in tone.

"Hillary Clinton did not say Bernie Sanders was 'not qualified.' But he has now - absurdly - said it about her. This is a new low," campaign spokesman Brian Fallon tweeted.

In addition to a trove of delegates New York is an important symbolic contest. Sanders was born in the Empire State, and New York City has been at the center of the national political battle over income inequality -- a signature issue for the Vermont senator. But Clinton represented the state in the Senate, and her campaign headquarters is based in Brooklyn.

CNN's Dan Merica and Julia Manchester contributed to this story.

Read this article:
Bernie Sanders: Hillary Clinton is not 'qualified' to be ...