Poll: Kamala Harris' support plummets after Democratic debates, Joe Biden expands lead

WASHINGTON – A new CNN poll shows that former Vice President Joe Biden's lead in the Democratic field has increased, while Sen. Kamala Harris, D-Calif., saw her support among registered Democratic and Democratic-leaning voters drop by 12 percentage points since June.

Biden's support increased by seven percentage points as 29% of Democratic and Democratic-leaning voters said they would vote for Biden, according to the poll by CNN and the survey firm SSRS.

Five percent of the voters surveyed said they backed Harris, down from the 17% support she enjoyed in June, when Biden and Harris sparred over Biden's previous comments about segregationist senators during the first Democratic debate.

Sen. Bernie Sanders, I-Vt., and Sen. Elizabeth Warren, D-Mass., had the second and third largest pools of support, respectively. Fifteen percent of respondents said they'd vote for Sanders, and 14% favored Warren.

Former Housing and Urban Development Secretary Julián Castro polled at 2% in this survey, meaning that he qualified for the third Democratic presidential debate in Houston, Texas, in September.

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Castro reacted to the news on Twitter on Tuesday morning, thanking all of his supporters.

The third Democratic presidential debate has harder cutoffs than the previous debates, as candidates have to hit 2% in four national polls and have at least 130,000 small donors.

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