With both presidential nominations virtually locked up and few burning issues on the ballot, about half of Sonoma County's voters are expected to sit out Tuesday's election, officials and observers say.
Voter turnout will be 50 to 53 percent, county elections chief Janice Atkinson predicted Monday, as absentee ballots continued coming in at a below-average rate.
"There aren't enough compelling issues on the ballot to draw people out," said Atkinson, who has been involved in county elections for nearly 40 years.
Some local experts put the turnout even lower, in the high 40 percent range, and Atkinson conceded: "They could be right."
Three supervisorial races, two congressional seats and four state legislative contests are in play, along with just two statewide ballot measures.
With President Barack Obama and Republican Mitt Romney almost certain to meet in November, the primary election's main event won't motivate many voters, Atkinson and the experts said.
In 2008, when California held its presidential primary in February, Sonoma County voter turnout was 76 percent.
Participation in the June, 2010, gubernatorial primary was 51 percent.
Atkinson said her forecast was buttressed, in part, by the slow return of absentee ballots, officially known as vote-by-mail ballots.
Of the 163,115 absentee ballots mailed to voters, just 63,894 valid ballots — 39 percent — had been returned on Monday, she said.