County election officials and observers anticipate that around three-quarters of the San Diego region's registered voters will cast votes in Tuesday's general election.
County Registrar of Voters Michael Vu said he expects turnout to be around 72 to 77 percent. He said nearly half of about 1.1 million mail ballots issued by his office had been returned so far.
The turnout among registered voters in the 2008 general election in San Diego County was 83.72 percent, according to the California secretary of state. It was 76.98 percent in 2012.
John Nienstedt of Competitive Edge Research & Communication said he expects the turnout percentage will push 78 percent in San Diego County overall, and 75 percent in the city of San Diego.
Elections analyst Vince Vasquez told City News Service that county turnout could be around 79 to 82 percent, which would be within the recent historic range.
Both he and Nienstedt said the sheer size of the ballot could lead to more "under-voting," in which San Diegans vote for president and other major offices, but neglect to decide on some local races and propositions.
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"The resulting volatility may give us some surprises on Election Night," said Vasquez, who thinks it will be mostly older voters who complete their ballots.
"If it's mostly older Democratic and Republican voters voting in down-ticket races, there is likely to be a higher skepticism and scrutiny of candidates and ballot measures," Vasquez said. "That probably results in more 'no' votes on local measures, and a higher deference to incumbents — with exceptions."
He said challengers and campaigns with sophisticated voter-targeting techniques and sufficient financial resources may be able to overcome the phenomenon, or make their races closer than they otherwise would be.
Nienstedt said the size of the ballot could intimidate some into not voting at all, but the importance of the issues involved in state and local measures — like legalizing recreational marijuana and raising the hotel room tax to pay for a football stadium of the Chargers — will motivate most people to complete their ballots.
"The solid turnout means voters are gamely taking on the `YUUUGE' 2016 ballot, as well as the stench of the presidential campaigns," Nienstedt said. "The vast majority of San Diego's registered voters will hold their nose and do their civic duty."
Polls open around the county at 7 a.m. and close at 8 p.m.
