Nearly half of Bernie Sanders' supporters say they won't support Hillary Clinton. | AP Photo Sanders again stops short of endorsing Clinton

Sen. Bernie Sanders still isn't giving his full-throated endorsement to Hillary Clinton as his campaign continues to hash out details of the Democratic Party platform, but Sanders did maintain that many of his primary supporters will "come on board" to back Clinton in November, if she embraces more of his policy issues.

"What I think is that if Hillary Clinton — and this is what we’re trying to do right now — we’re trying to say to Secretary Clinton and to the Clinton campaign: Make it clear which side you are on," Sanders said Sunday on CNN's "State of the Union."


"Stand up, be bolder than you have been, and then many of those voters, in fact, may come on board."

Sanders pointed to higher education, where Clinton "has some good ideas," but "it doesn't go far enough," insisting that Clinton should support "free tuition at public colleges and universities." He also listed a $15 minimum wage and health care for all as other policy issues he'd like her to embrace.

"So it’s not just Bernie Sanders saying, ‘Oh, yeah, vote for Hillary Clinton,’ it is Hillary Clinton standing up and saying, ‘You know what, these are the things we need to do,’" Sanders said. "And if she does the right thing, I’m absolutely confident that the vast majority of my supporters will vote for her. That’s the process we’re engaged in right now; we’re working on the Democratic platform."

Last week, Sanders, who hasn't formally conceded the Democratic primary, told multiple cable outlets that he would vote for the former secretary of state, but he hasn't endorsed her "because I haven’t heard her say the things that I think need to be said.”

Nearly half of Sanders supporters say they won't support Clinton, opting for Trump or libertarian Gary Johnson instead, according to a Bloomberg poll released last week.

When asked on CNN on Sunday if that hesitation might be confusing to supporters, Sanders insisted that he was engaged in two efforts: building a progressive political movement and defeating Donald Trump.

"I am going to do everything that I can to defeat Donald Trump, but a lot of that responsibility about winning the American people over to her side is going to rest with Secretary Clinton," Sanders said.

Sanders also weighed in on Brexit, noting that there is "massive resentment throughout Europe and U.K. and in United States about a global economy which works well very, very well for large multinational corporations" but "is not working in many ways for middle class and working families in this country," mirroring the sentiments that bolstered his own political campaign.

"What ordinary people are saying is, ‘Hey, give us an economy that works for all of us, and not just to the people on top,'" Sanders said. "And I think that is, to a significant degree, what this Brexit was about."