Story highlights That's a reversal from Monmouth's last poll, in November, that had Clinton up 48% to 45%

The independent senator also leads among independent voters

Washington (CNN) Sen. Bernie Sanders has widened his lead over Hillary Clinton in the New Hampshire Democratic primary to 14 points, according to a new poll out Tuesday.

A Monmouth University survey finds the Vermont senator leading Clinton 53% to 39% in the early voting state.

That's a reversal from Monmouth's last poll, taken in November, that had Clinton up 48% to 45%, though Sanders led in September by 7 points.

Sanders also has an advantage in the firmness of voters' decisions. Of those who support Sanders, 55% say they have made up their mind, while 49% of Clinton supporters say the same.

Former Maryland Gov. Martin O'Malley, the only other Democratic candidate, was at 5%.

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