A new poll shows Democratic presidential candidate and Vermont Senator Bernie Sanders leading by five points over rival Hillary Clinton in Iowa. Just weeks before the Iowa caucuses, the survey from Quinnipiac University found 49 percent of likely Democratic caucusgoers back Sanders versus 44 percent for Hillary Clinton. Meanwhile, the latest New York Times/CBS News poll shows Clinton’s lead over Sanders nationally has virtually disappeared. And members of the progressive advocacy group MoveOn have voted to endorse Sanders by the largest margin in the group’s history. A record 78.6 percent of more than 340,000 MoveOn voters backed Sanders. Meanwhile, Hillary Clinton has taken aim at Sanders’ plan for single-payer healthcare, calling it "risky." At a campaign event, Clinton’s daughter, Chelsea Clinton, claimed that Sanders wants to dismantle Obamacare. Sanders attributed the attack to his surge in the polls, saying the Clinton campaign is "in serious trouble."