Sen. Bernie Sanders is expanding his lead in New Hampshire — as former Vice President Joe Biden falters, according to a new poll released on the eve of the primary election in the Granite State.

Sanders, who won New Hampshire in 2016, has 25 percent support — an increase of two percentage points from a week ago — while Biden dropped eight percentage points to 14 percent, a UMass Lowell Center for Public Opinion poll showed.

Former South Bend, Ind., Mayor Pete Buttigieg finished in second place with 17 percent, followed by Sen. Elizabeth Warren of neighboring Massachusetts with 15 percent.

That’s a five percentage-point jump for Buttigieg, but a four-point drop for Warren from a week ago.

Rounding out the Democratic field are Sen. Amy Klobuchar of Minnesota with 8 percent and businessman Tom Steyer at 5 percent.

No other Democratic presidential hopeful polled higher than 5 percent.

Sanders is tops among voters 18 to 44 with 34 percent, and with those 45 and older with 22 percent — but Buttigieg’s support is more balanced at 15 percent of those 18 to 44 and 17 percent of those 45 and older.

Sanders, 78, also leads among liberal voters, drawing 31 percent support.

Buttigieg, 38, comes in behind Sanders with 21 percent.

Sanders, a progressive who advocates for Medicare for all, tied Biden among moderate voters with 19 percent.

Tuesday’s New Hampshire vote is the first since the mistake-prone Iowa caucuses last Monday in which Buttigieg won the most delegates but Sanders bested him in the popular vote.

Three-time New York Mayor Michael Bloomberg isn’t competing in New Hampshire.

The poll was conducted Feb. 4 to 7 and surveyed 440 likely Democratic primary voters from New Hampshire.

It has a margin of error of 6.5 percentage points.