After first round of debates, Kamala Harris moves into second place, hot on the heels of Joe Biden

Two new polls show Democratic presidential hopeful Sen. Kamala Harris (Calif.) gaining ground on current front-runner and former Vice President Joe Biden.

Here's what we know

A Quinnipiac poll published on Tuesday showed Harris polling at 20 percent, within two points of Biden (22 percent). This poll had a margin of error of +/- 5 percent. Sen. Elizabeth Warren (Mass.) was next at 14 percent, followed by Sen. Bernie Sanders (Vt.) at 13 percent. This is the first time that Harris has ever polled over 8 percent.

The rest of the candidates trailed in single digits: South Bend, Indiana, Mayor Pete Buttigieg at 3 percent, Sen. Cory Booker (N.J.) at 3 percent, and the rest at 1 percent or lower.

The last Quinnipiac poll, taken at the beginning of June, had Biden with a strong lead at 30 points, double that of Sanders who was his nearest competition. In that poll, Harris was only at 7 percent.

This poll isn't an outlier

This new Quinnipiac poll echoed the results of a CNN poll published on Monday, which showed Biden at 22 percent (down 10 points) and Harris at 17 percent (up 9 points). Warren also made gains in the CNN poll, from 8 points to 15 percent, while Sanders was down 4 points to 14 percent. The margin of error for this poll was +/-4.7 percent.

A CNN poll from May had Harris at only 8 percent.

During the NBC News Democratic debate on June 27, Harris targeted Biden. Challenging the former vice president on his civil rights record, Harris talked about a little girl who had to be bused to a newly-desegregated school.

"That little girl is me," she said.

Her debate performance overall was considered to be strong, which may have helped her polling.