John Upton/The Bay Citizen

Voters cast ballots in a Potrero Hill neighborhood firehouse at the corner of Vermont and 16th streets on Nov. 7, 2010.

California Secretary of State Debra Bowen, the state’s top elections official, will dispatch elections observers on Tuesday to monitor polling places throughout San Francisco, her office said Monday.

In mid-October, several mayoral campaigns jointly called on Bowen to send observers after Mayor Ed Lee’s supporters were filmed in Chinatown helping elderly voters fill out their ballots. Several campaigns condemned the actions as illegal ballot tampering and elections fraud. District Attorney George Gascon has opened a preliminary investigation into the incidents.

“The Secretary of State has generally heard from a variety of San Franciscans concerns that have been raised about tomorrow’s election,” said Nicole Winger, a spokeswoman for Bowen. “They will serve as extra eyes and ears on the ground.”

Winger said that the Secretary of State’s decision was not in response to the letter.

She would not say how many monitors will be on duty or where they will be working.

Last week, John Arntz, the Director of the Department of Elections, told the Examiner that it is "not uncommon" for observers to monitor the city's elections.