WASHINGTON – With the New Hampshire primary nearly a month away, there is no clear frontrunner in the Granite State, according to a poll released Thursday.

Pete Buttigieg, the former mayor of South Bend, Indiana, leads the Democratic field with 20% support among registered New Hampshire Democrats and unaffiliated voters who are likely to participate in the February 2020 Democratic primary, according to a Monmouth Poll published Thursday. He is followed closely by former Vice President Joe Biden with 19%. Sen. Bernie Sanders of Vermont earned 18% support, while Sen. Elizabeth Warren of Massachusetts had 15%.

The New Hampshire primary takes place on Feb. 11 and likely will be influenced by the Iowa caucuses, which take place eight days before.

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Buttigieg and Sanders saw the most growth since the last New Hampshire poll from Monmouth University in September. Buttigieg saw a 10 percentage point increase, from 10% support in September, while Sanders saw a 6 percentage point increase from 12%.

Biden and Warren saw their support drop from the September poll. Warren fell 12 percentage points from 27% and Biden dropped 6 points from 25%.

The next highest candidate in this month's poll is Sen. Amy Klobuchar of Minnesota at 6%. Rep. Tulsi Gabbard of Hawaii and political activist Tom Steyer are both at 4%. Entrepreneur Andrew Yang followed at 3%. Colorado Sen. Michael Bennet was at 2%, while Sen. Cory Booker of New Jersey was at 1%. Three candidates earned less than 1%: former Massachusetts Gov. Deval Patrick, former Maryland Rep. John Delaney and author Marianne Williamson.

Patrick Murray, director of the independent Monmouth University Polling Institute, said in a statement that “the race remains fairly wide-open."

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"To the extent that New Hampshire voters could take some cues from Iowa, it’s also worth keeping an eye on lower polling candidates like Klobuchar if any of the leading contenders stumble in the earlier Iowa contest,” Murray said.

The poll was published a day before the deadline to make it to Tuesday's debate in Iowa, which several candidates are still trying to qualify for. Booker, Gabbard, Steyer and Yang still all need multiple polls to qualify.

Candidates needed to get 5% in at least four national or early-voting state polls, or at least 7% in two early-voting state polls, which includes Iowa, New Hampshire, Nevada and South Carolina.

The poll was conducted by telephone from Jan. 3 to 7, with 697 registered voters contacted. Of those contacted, 404 were New Hampshire voters who are likely to vote in the Democratic presidential primary in February 2020. There is a margin of error of plus or minus 4.9 percentage points.