Hillary campaign boss: Obama voters are on board

Hillary Clinton is finding broad support on the 2016 presidential campaign trail not just among older Democratic voters, but with the young Americans who were instrumental in electing President Barack Obama, the Democratic candidate's campaign manager said Wednesday.

"That coalition of voters that was so strong for Obama, including young people, we're seeing in the polling and as Hillary is out campaigning, they're on board," Robby Mook told CNBC's "Squawk Box."

Voters are looking for a president who will be a champion for everyday people, Mook said. For young voters, that means creating the conditions that will allow them to get a college education without taking on debt and find employment after graduation, he added.

For seniors, it means standing up for Social Security and Medicare, two entitlement programs Clinton has a track record of protecting, Mook said.

Eighty-one percent of Democrats view Clinton favorably, versus just 6 percent of the party who disapprove of her, according to an NBC News/Wall Street Journal poll released Monday. Negative views of Clinton have risen slightly among the general public, according to the poll.

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Clinton has recently faced criticism over her use of a private server to store her emails while serving as Secretary of State under Obama and how her family's charitable organization documented donations from foreign governments in tax filings.

The Clinton campaign is not taking the Democratic primary for granted and expects a robust contest, Mook said. He denied that Clinton is tacking to the left or right, but said Clinton is positioning herself as the champion of the everyday American.

Clinton reportedly said in a closed-door meeting that the economy required a "toppling" of the wealthiest 1 percent of Americans and has made comments critical of CEO pay.

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Mook said top-down economic policies that favor the wealthy and create corporate loopholes were responsible for crashing the U.S. economy and hurting everyday Americans.

"What Hillary has been very clear about is that the deck is still stacked against ordinary, everyday Americans," he said. "And so the question is how are we giving everyone that same opportunity so that the tax code is fair, so that people have the same opportunity to start a business, to get an education—that the middle class doesn't just get by, that they can get ahead?"

Later on "Squawk Box," GOP presidential candidate Carly Fiorina, the ex-Hewlett-Packard CEO, said there's a "huge gulf" between what the American people want for the country and what the government and the status quo is delivering.

Read MoreCarly Fiorina: Hillary would fuel crony capitalism

Clinton has also made a pathway to citizenship a defining issue in the 2016 campaign after a speech on Tuesday in which she voiced support for Obama's executive action to shield immigrants deportation, Mook said. In a speech, Clinton said she favors a route to U.S. citizenship rather than some other legal status.