Some 2.5 million ballots have yet to be counted in California from Tuesday's primary, according to figures released Thursday evening by the Secretary of State's office, which could push turnout closer to what officials predicted.

Of the 2,586,331 unprocessed ballots, 1,801,816 are vote-by-mail ballots, 705,489 are provisional ballots and 79,026 are ballots with damage, those that couldn't be read by machine or require further review.

Voters could send in vote-by-mail ballots as late as June 7, meaning some may not arrive for counting until Friday.

Counties have until July 8 to canvass the ballots and certify the results for the Secretary of State's office. The Secretary of State then has until July 15 to issue a statement of vote and certify the results statewide.

Locally, Los Angeles County has 616,056 unprocessed ballots, according to the Secretary of State's office, or about 46,000 more than estimated on Wednesday.

The Los Angeles County Registrar-Recorder/County Clerk's office is scheduled to provide an update for the county on Friday.

Orange County has 206,285 unprocessed ballots, according to the state data. Of those, 144,915 are vote-by-mail ballots and 61,370 are provisional ballots. The county reported zero ballots with damage.

There are enough unprocessed ballots that turnout could climb several percentage points higher than the current, unofficial statewide turnout of 33.6 percent, and in turn, increase turnout in each of the state's 58 counties. And should all the ballots be certified, turnout would come in at about 48 percent statewide.

Hopes for a strong turnout were high. Prior to the election The Field Poll forecast turnout at about 45 percent. In Los Angeles County, Registrar-Recorder/County Clerk Dean Logan sent a tweet shortly after the polls closed Tuesday estimating turnout at roughly 40 percent.

Experts say voter participation likely didn't live up to a record number of registrations, partly because presidential primaries were settled.

Ballots counted on Tuesday already marked an increase in L.A. County turnout over the last two primaries. In 2014, a dismal 17 percent of the county's registered voters cast ballots. And in the 2012 presidential primary, just 21.8 percent of registered voters in L.A. County cast ballots.

It also reversed a downward trend for L.A. County turnout in statewide primaries. Turnout has regularly been below 50 percent since the 1980s, and below 40 percent since 1996. The one bright spot was 2008, when 55 percent of L.A. County voters cast ballots. Hillary Clinton also won in California that year.