The UC Berkeley Institute of Government Studies poll co-sponsored by the Los Angeles Times shows Caruso polling at 24% and Bass at 23% of likely voters.
If those numbers held in the primary, the race would move to a runoff in November.
The poll, taken from March 29 through April 5, shows a dramatic shift in just two months, after Bass previously held a wide lead over Caruso in the same IGS poll.
"Rick Caruso doesn't only have money and he doesn't only have an appealing message, he has both," said Loyola Law School professor Jessica Levinson. "And that right now has lead to an exponential growth in his support. Now, will that hold? It's April."
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City Council Member Kevin De León places distant third at 8%. Council Member Joe Buscaino and City Attorney Mike Feuer, who both polled at 4% in the previous survey, are now at 1% and 2%, respectively.
Caruso's strong polling comes as he's flooded the television and digital markets with nearly $9 million in advertisements, while Bass has yet to air any television ads.
According to the survey, the top issue influencing voters is homelessness, cited at 61% of likely voters.
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In a statement, Karen Bass's spokesperson said:
"I have no doubt that if Congresswoman Bass had $10 million to spend, her polling numbers would have tripled, too. Caruso has shattered every record for Mayoral campaign spending, Bass hasn't spent a dime on paid ads -- but they're neck and neck. In a city increasingly defined by inequity, Angelenos understand the difference between a candidate who has to earn their support and someone trying to buy votes with their personal wealth."
But Monday's poll shows Caruso's stance on public safety is resonating as he has four times the support to address the rise in crime over Bass.
In a statement, Caruso's campaign said:
"Today's poll shows what we are seeing around Los Angeles. Rick Caruso's commitment to dealing with homelessness, crime, and corruption at City Hall is leading to fast growing support with voters. L.A. needs a Mayor that doesn't work for special interests to solve our problems. Rick Caruso can clean up L.A., his only special interest is Los Angeles."
The primary is set for June 7.