Online sports gambling companies, California tribes and card rooms have spent more than $410 million on a pair of dueling ballot measures to legalize sports betting in person and online.

If either side thought Proposition 26 or 27 could win, they placed a bad bet. A new poll from the UC Berkeley Institute of Governmental Studies, co-sponsored by The Times, shows little chance voters will approve either measure in November.

Likely voters who said they had seen a lot of ads about the propositions were more opposed to the measures than those who had not seen any ads.

“I think it’s the negative advertisements that have kind of been turning voters away,” said Berkeley IGS poll director Mark DiCamillo.