CNN released a poll on Tuesday that shows support for Democrat presidential hopeful Sen. Kamala Harris (D-CA) has dropped 12 points. In June Harris had 17 percent support but the poll reveals a steep decline among supporters after the second debate to just 5 percent.

“That’s similar to the level of support she had in the spring before a surge following her initial debate performance,” CNN reported on its poll. “The June CNN poll was conducted in the days immediately following the first round of Democratic National Committee-sanctioned debates among the presidential candidates.”

A graph included in the CNN report on its poll, conducted August 15 through 18 among a “random national sample” of 1,001 adults by phone, shows most leading candidates maintaining or increasing support but Harris’ support in falling dramatically.

Sens. Bernie Sanders (D-VT) and Elizabeth Warren (D-MA), for example, had 15 percent and 14 percent, respectively, in June and came in at the same percentage of support in this poll.

The poll also shows South Bend Indiana Mayor Pete Buttigieg with the largest single-digit percentage at 5 percent — up for 4 percent in June.

Despite ongoing gaffes and revelations about his health, former vice president Joe Biden regained a large lead in the CNN poll coming in at 29 percent support, almost double that of second-place Sanders at 15 percent.

Biden had 22 percent support in CNN’s June poll.

But Biden’s support isn’t across the board, according to CNN:

Biden’s advantage in the poll is boosted by stronger support from self-identified Democrats (31%) than from independents (23%), older voters (34% among those age 45 and older) than younger ones (23% among those under age 45) and from moderate and conservative voters (34%) than liberals (22%). Among liberals, in fact, the race is a near three-way tie: 23% choose Warren and 22% each back Biden and Sanders. No other candidate even hits 5% among this group.

The poll, which is one that the DNC deemed qualifying for its rule of 2 percent poll support in four polls, also puts Julian Castro on the third debate stage in Houston in September.

Rep. Tulsi Gabbard (D-HI), who took on Harris in the second debates, now has two qualifying polls including the CNN poll but she needs two more to make it to the debate stage.

The full sample poll has a margin of error of plus or minus 3.7 percentage points and the subsample of 402 Democrats and Democrat-leaning, registered Independents is plus or minus 6.1 percentage points.

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