Populist Vermont Sen. Bernie Sanders is on a roll, more than doubling his support in Iowa where the Democratic race is coming down to the independent against Hillary Rodham Clinton, with others like Vice President Joe Biden and former Maryland Gov. Martin O’Malley becoming irrelevant.

In a new Quinnipiac University poll of likely Iowa caucus-goers released Thursday, Clinton continues to lead, 52 percent to 33 percent for Sanders.