Despite assurances from California election officials that the state’s election system is among the most secure in the country, some Trump backers still plan to monitor the polls in person on Election Day.

Mary Henderson, head of the Trump campaign for Riverside and San Bernardino counties, told KPCC on Thursday that she is frankly worried about voting security issues — and so are the many Republicans she talks to.

"One-hundred percent of the people that call me, or at least 99 percent," she said, "is someone that’s concerned."

Henderson said she knows of several dozen Trump volunteers who will travel to Riverside to monitor the polls for any problems. 

There are more than 100,000 Trump volunteers in California, according to Trump’s California communications director Jon Cordova. Cordova said the campaign emphasizes nonviolence in its messaging to its volunteers.

But he said recent events, like the damage to Trump’s star on the Hollywood Walk of Fame, have some on edge.

"We’re careful about our volunteers to make sure we don’t put them in harm’s way...it is a concern," he said.

Others worry Trump’s rhetoric may spur his supporters into violence. Several of Trump events, including a rally he held in Costa Mesa in April, have turned violent with supporters or protesters clashing with police or each other.

Meanwhile, hundreds of nonpartisan volunteers will also be monitoring polling locations in California on election day.

Asian Americans Advancing Justice California, a nonpartisan group that advocates for Asians and voting rights, plans to send 600 trained volunteers to polling places in 25 counties, including Riverside and Orange, to help voters with limited English proficiency.

But the group also said volunteers will be on the lookout for voters who are "intimidated or harassed, and if voters are being asked to show  identification inappropriately, among other issues,” Deanna Kitamura, the group's Voting Rights Project director, stated in a news release.

“If our monitors observe or report any major issues, we will be in immediate contact with election officials on Election Day," Kitamura said. "We want all voters to be able to cast an informed ballot and to have a positive experience in this election."

Karin Wang, Advancing Justice Los Angeles vice president of programs and communications, added: “I think all of us have a pretty strong fear that we might see things this year that we haven’t seen in the past.”

The National Association of Latino Elected and Appointed Officials Educational Fund (NALEO) recently asked the Justice Department to help ensure disruption-free elections. 

“What we are most concerned about is anybody who takes it upon themselves to be their own poll watchers, and to try to determine who is and who is not eligible to vote simply because of their appearance," said Arturo Vargas, executive director of NALEO, a nonpartisan group based in Los Angeles.