Hillary Clinton continues to hold a wide lead over Donald Trump among California voters, support to legalize recreational marijuana is tenuous, and a large block of voters aren’t sure who they want for U.S. Senate, according to a poll conducted by SurveyUSA and issued Monday by Southern California News Group and KABC/Eyewitness News.

The state poll shows Clinton beating Trump 56 percent to 30 percent among likely voters. If Trump’s total holds he could become the least popular GOP presidential nominee in state history.

“The low-water mark is currently held by George Herbert Walker Bush, who got 33 percent of the popular vote in California in a three-ways contest in 1992,” according to an analysis by SurveyUSA.

About 7 percent of likely voters are undecided about who they want for president, double the number of undecided voters found when the previous SurveyUSA poll was conducted, 17 days ago, just after the first presidential debate.

The latest SurveyUSA poll also shows state Attorney General Kamala Harris ahead of Rep. Loretta Sanchez, D-Orange, 45 percent to 24 percent. That’s a dramatic increase over the 11-point lead held by Harris in the earlier poll.

Other polls have wavered in the size of Harris’ advantage, with the only consistent findings being her strong lead and the large number of undecided voters. A September poll by Field showed Harris with a 22-point lead, while won by the Public Policy Institute of California showed the lead at 7 points.

But the new SurveyUSA poll also found nearly one third of voters polled are undecided about their choice to replace Barbara Boxer in the U.S. Senate, possibly a reflection of Republicans failing to engage in a race that features two Democrats.

Another key ballot initiative, Prop 64, which would legalize the recreational use of marijuna, shows support described as “fragile” by Survey USA. About 51 percent of voters favor the measure, while 40 percent oppose, the poll found. About 9 percent remain undecided.

Support for ballot measures tend to slip closer to election day.

Three other ballot measures were polled:

Support of Proposition 56, which would increase the tax on a package of cigarettes by $2, has slipped 6 points but still leads, 57 percent to 35 percent.

Proposition 62, which would end the death penalty in California, trails by 18 points and is headed for defeat, according to the SurveyUSA analysis.

Proposition 63, which would outlaw large-capacity magazines and requires background checks on ammunition purchases, leads by more than a 2-1 margin and is expected to pass, the analysis says.

The poll, conducted Oct. 13, 14 and 15, surveyed 725 likely voters from throughout the state with a 3.7 percent margin of error. Of those, 58 percent were interviewed on their home phones by an automated recording. The remaining 42 percent, who could not be reached on a home phone, responded to a questionnaire sent to their smart phone, tablet or other electronic device.

Contact the writer: mwisckol@ocregister.com