Story highlights Bernie Sanders says he still won't attack Hillary Clinton on her "damn emails" because voters want to hear about other issues

But Sanders has opened up attacks on Clinton in other areas, accusing her of being a latecomer to liberal causes

Washington (CNN) Bernie Sanders has opened up his line of attack on Hillary Clinton, accusing her of being a latecomer to popular liberal causes and railing about her taking corporate donations. But there's one item off the table: her "damn emails."

"I think the American people get tired of seeing front page stories from the media day after day about emails," Sanders told CNN's Gloria Borger for an interview airing Monday on "New Day." "They want to know why their kids can't afford to go to college. They want to know why they can't afford health care, why we have the grotesque level of income and wealth inequality. That's what they want."

Pundits knocked Sanders in the first Democratic debate for effectively handing Clinton a free pass on what has been perhaps the most damaging issue of her candidacy, her secret use of a private email server to conduct government business.

"I do not regret that at all," he said of his debate comment.

But he's been ramping up the heat on other issues, in a notable departure from earlier in the campaign, when he largely avoided even glancing shots.

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