Sen. Bernie Sanders (I-Vt.) has jumped out to a commanding lead over his 2020 Democratic primary opponents in New Hampshire, according to a new CNN poll of the early primary state.

The survey, which was released on Sunday and conducted by New Hampshire University, found that 25 percent of likely Democratic primary voters favor the progressive Vermont senator, a four-point increase from October. Sixteen percent of respondents said they would pick former Vice President Joe Biden to be the Democratic nominee.

Former South Bend, Ind., Mayor Pete Buttigieg earned a five-point boost in support to 15 percent, surpassing Sen. Elizabeth Warren (D-Mass) to come in third. Warren, who placed second in New Hampshire in an identical poll from October, appeared in fourth with 12 percent support. The figure represents a 6-point slide over the last few months for the Massachusetts senator.

Sanders, Biden, Buttigieg and Warren were the only candidates to register double-digit support among Democrats. Sen. Amy Kobuchar (D-Minn.) earned 6 percent support, while Rep. Tulsi Gabbard (D-Hawaii) and tech entrepreneur Andrew Yang earned the backing of 5 percent of voters. The result qualifies Yang for the February Democratic debate.

The New Hampshire survey comes as polls increasingly show Sanders in position to contend with Biden for the Democratic nomination. A new Washington Post-ABC News survey showed that the two are the only candidates registering at least 20 percent support nationally among Democratic leaning voters. In addition, recent polls have shown Sanders neck and neck with Biden in Iowa.

A WBUR News survey released last week also found Sanders with a double-digit lead over the field in New Hampshire, the second state to hold a presidential primary.

CNN noted that Sanders has increased his support (13 percentage points) among liberal likely primary voters in New Hampshire. This has come at the expense of Warren, whose support among that block has slid by seven points. In total, 39 percent of liberal likely primary voters favor Sanders, while 21 percent back Warren.

Thirty-nine percent of likely Democratic primary voters say Sanders will win the New Hampshire primary. But 49 percent of respondents acknowledge that they are still considering their selection. Sanders won New Hampshire by more than 20 points during the 2016 Democratic presidential primaries.

The CNN poll was conducted between Jan. 15 and Jan. 23 among a random population of 1,176 adults in New Hampshire, including 516 likely Democratic primary. The margin of error is 4.3 percent.