The official election night returns were that just 3.2 million or 18.3 percent of the state's 17.7 million registered voters cast ballots, but those numbers will increase when the number of still-uncounted ballots becomes clear in the next few days.
"I'm going to be surprised if it doesn't get to 20 or 23 percent," Paul Mitchell, a political number analyst for Political Data, Inc., said Wednesday.
Reaching 23 percent would mean another 800,000 or so ballots, mostly mail-in ballots delivered to election officials in the final hours of the election, remain to be counted.
However, even were turnout to reach 23 percent, that still would be five percentage points below the lowest statewide primary turnout ever recorded, 28.22 percent in June, 2008.
That was a presidential election year, when turnout usually rises, but California held its presidential primary in February that year, hoping to become more relevant in the selection of presidential candidates, while legislative, congressional and local primaries were held in June.
Four years ago, when California was last filling its statewide offices, the turnout was 33.63 percent.
Initial turnout tallies varied widely among California's 58 counties this year, ranging from a high of 69.5 percent in the state's smallest county, Alpine, to a low of 13.1 percent in its largest, Los Angeles - not counting the ballots yet to be counted.
PHOTO:Charles Rich, 61, of West Sacramento votes in a room at fire station #45 on Tuesday, June 3, 2014 in West Sacramento. The Sacramento Bee/Randy Pench.