Poll: Half of voters have changed their minds

WASHINGTON — As Democratic presidential hopefuls prepare for their second round of debates this week, a new poll finds that half of likely primary voters have changed their minds since the spring, highlighting how unsettled the contest remains.

Former Vice President Joe Biden continues to lead in the latest University of Southern California Dornsife/Los Angeles Times nationwide poll, while three senators, Kamala Harris of California, Elizabeth Warren of Massachusetts and Bernie Sanders of Vermont, are essentially tied for second place. That marks an improvement for Harris and Warren and a decline for Sanders since April, when the poll last tested the Democratic race.

More notably, about half of the voters in the poll have changed their preferences since the April survey — a reminder that at this point of the campaign, most voters don’t have firm commitments.

Voters at this stage of the campaign are “corks on the water floating around,” said Mike Murphy, the longtime Republican strategist who is co-director of USC Dornsife’s Center for the Political Future, one of the sponsors of the poll. That’s particularly true for voters nationwide, who have less exposure to the candidates than voters in states with early primaries.

The volatility has a limit, however. The vast majority of voters who switched since April moved among the top four candidates or between them and undecided status. The mass of candidates languishing at 1% or lower hasn’t benefited.

Biden continues to lead the poll, with 28%. Harris was at 10%, putting her in an effective tie with Warren, also at 10% and Sanders, at 11%. An additional 25% of voters said they were undecided when presented with a list of 25 people who have declared they are running.

Beyond the top candidates, the poll found Pete Buttigieg, the mayor of South Bend, Ind., and former Rep. Beto O’Rourke of Texas having more than 1% support. Buttigieg’s support has grown since April and now stands at 5%, while O’Rourke’s has shrunk to 3% — all shifts within the poll’s margin of error.

“When your front-runner is at 28% and undecided is at 25%, it’s a pretty fluid race,” said Jill Darling, the poll director.

Unlike other public opinion samples, the USC/L.A. Times poll surveys a panel of more than 7,000 members, tracking their views over time. Polls using the panel can look at how and when specific voters have changed their preferences.

In the primary contest so far, the first round of debates in June appears to have played a big role in changing minds. Harris, in particular, gained support among people who watched the debate, during which she forcefully challenged Biden over his nostalgia about working with segregationist senators early in his career. The exchange appears to have boosted Harris without doing longterm damage to Biden, who gained roughly as many supporters as he lost.

People who reported that they watched the debate — about 3 in 10 of those who said they planned to vote in a Democratic primary — were more likely to have switched than others. But even many voters who did not watch the debate changed their minds.