Hillary Clinton’s tour promoting her book Hard Choices may be having an effect—though perhaps not the one the 66-year-old former secretary of state might have wanted. A new poll of the potential 2016 presidential field from Quinnipiac, conducted at the end of June, found support for Clinton among Democratic primary voters at 58 percent. That’s an 11-point drop from an ABC News/Washington Post poll of the potential Democratic field—conducted in late May, before Hard Choices was released—that found 69 percent supported Clinton over any other possible Democrats.

According to the Quinnipiac poll, the biggest beneficiary of Clinton’s drop in support appears to be Elizabeth Warren, the first-term senator from Massachusetts and a favorite of progressive populists. Warren received 11 percent support, while Vice President Joe Biden has 9 percent. Governor Andrew Cuomo of New York received four percent, while governor Martin O’Malley of Maryland and former governor Brian Schweitzer of Montana each polled just one percent.