Sanders, with 25% support among Democrats and Democratic-leaning independent voters, has ticked up four percentage points since a late January poll from Quinnipiac, while other candidates have lost support.
Following Sanders are former Vice President Joe Biden with 17% support, former New York City Mayor Michael Bloomberg at 15%, Massachusetts Sen. Elizabeth Warren with 14%, former South Bend, Indiana, Mayor Pete Buttigieg with 10% and Minnesota Sen. Amy Klobuchar with 4%. No other candidate receives above 2% in the poll.
While Biden is down nine percentage points since January, Bloomberg has seen significant growth, up 7 percentage points -- nearly doubling his 8% support.
Bloomberg is doing especially well among black Democratic voters, with 22% support, rivaling Biden's 27%. The former vice president has been known for doing well among black voters throughout the 2020 campaign cycle. Biden had 49% support among black voters in January, with the latest polll marking his biggest loss among any demographic group since the January poll.
Sanders' lead comes the day before the New Hampshire primary, a state in which he is doing well in the polls, and on the heels of a strong showing in Iowa.
Other national polls have shown Bloomberg climbing while Biden's support wanes, but most statewide polls -- including in New Hampshire -- don't include Bloomberg since he won't be on the ballot.
But more than half (56%) of Democrats and Democratic-leaning independent voters say they still might change their mind before the primary; 42% have made up their mind.
The Quinnipiac University poll, conducted February 5-9 among 1,519 self-identified registered voters nationwide with a margin of error of +/- 2.5 percentage points. The survey includes 665 Democratic voters and independent voters who lean Democratic with a margin of error of +/- 3.8 percentage points.