SAN DIEGO A new poll confirms that a tight three-way race is developing in Californias key Democratic presidential primary, with one candidate showing impressive momentum: Sen. Elizabeth Warren of Massachusetts.

A survey released Thursday by the Public Policy Institute of California showed Warren the choice of 23% of likely primary voters, with former Vice President Joe Biden at 22% and Sen. Bernie Sanders (I-Vt.) at 21%. When the Democratic race was first taking shape in the spring, a Quinnipiac Poll had shown Warren in single digits in the Golden State, far behind Biden, Sanders and California Sen. Kamala Harris .

Indeed, as Warrens support has surged in California as it has nationally the prospects for Harris in her home state have taken a hit, again reflecting national trends. Perhaps the new polls most striking finding is that Harris trailed well behind the pack with just 8% support, another sign of trouble for her struggling campaign.

Warren may well be a beneficiary of Harris collapse, said veteran California Democratic strategist Garry South. Since her very impressive debut (as a White House candidate) in Oakland in January, Harris has done little in California to solidify whatever support may have been potentially there for her.

Voters like Cindy Henderson, an author who showed up to hear Warren speak Thursday as the candidate made her first campaign stop in San Diego, give a glimpse into the races current dynamics.

I was actually a Kamala fan, Henderson said. Just something in the last two or three months, Im just kind of dropping off [on her]. I think shes not quite ready. I just dont think theres much depth yet. The more I hear and watch what Elizabeth does, its just like, OK, shes a rock star. Im loving her message.