While Biden’s standing has diminished since the most recent CNN poll in October, when he achieved 34 percent support among likely Democratic voters, so has Warren’s. In last month’s survey, the Massachusetts senator was the runner-up with 19 percent support, ahead of Sanders with 16 percent.

Warren had emerged in past weeks as a rising force within the Democratic nominating contest, even supplanting Biden in the first-place slot of some national surveys. But her performance in public polling has since eroded slightly amid heightened scrutiny of her ambitious, progressive policy prescriptions.

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At the same time, the more moderate Buttigieg has gained momentum, establishing himself as a top-tier primary candidate alongside Biden, Sanders and Warren, and cementing his status as a frontrunner in the first-in-the-nation caucus state of Iowa — despite concerns regarding his ability to attract minority voters.

The latest CNN poll comes after the release Tuesday of another national survey of Democratic voters by Quinnipiac University, which showed Biden earning 24 percent support, Buttigieg finishing second with 16 percent, Warren with 14 percent and and Sanders with 13 percent.

The CNN poll has no ramifications for next month’s primary debate, as the candidates who received at least 4 percent support — the polling threshold for national surveys — have already qualified to participate.

The televised forum on Dec. 19 is set to take place in Los Angeles and will be sponsored by POLITICO and PBS NewsHour.

The CNN/SSRS poll was conducted November 21-24, surveying a random national sample of 1,007 adults, including 431 registered voters who are Democrats or Democratic-leaning independents.

The margins of sampling error are plus or minus 3.7 percentage points for the full sample and 5.7 percentage points for results among potential Democratic voters.