Three special primary elections were held Tuesday to decide which candidates would advance under California's nonpartisan, top-two primary system. An initial count, according to California's secretary of state,

shows nearly 200,000 voters participated in Senate Districts 7, 21, and 37 by mail or at the polls.

Special elections are known for low voter turnout and these were no exception -- turnout is expected to be under 25 percent across the state.

Senate District 7

One Republican and four Democrats appeared on the ballot to replace now U.S. Representative Mark DeSaulnier in Senate District 7. By Wednesday morning, Democrats Steve Glazer and Susan Bonilla took the top two spots; Glazer placed first with 32.8 percent and Bonilla placed second with 24.9 percent, according to the secretary of state. Joan Buchanan, also a Democrat, took third with 22.6 percent.

The one Republican candidate, Michaela Hertle, dropped out over a month ago and endorsed Steve Glazer, but still managed to gather 17 percent.

Weeks after Hertle dropped out of the race, the Asian American Small Business PAC sent out controversial mailers that the California GOP says used trademark Republican images to make voters think Hertle was still actively campaigning. This may partially explain why she got so many votes.

Nearly a fourth (22 percent) of voters in the 7th district (comprised of Contra Costa and Alameda County) are registered No Party Preference. Democrats and Republicans account for nearly 43 percent and 28 percent, respectively.

After returns came in on election day, Glazer touted his credentials as a "bipartisan problem solver," best evidenced by the endorsement of his former Republican opponent, Michaela Hertle. Bonilla has lined up key endorsements of her own. The California Democratic Party and U.S. Rep. DeSaulnier have endorsed her.

The general election between the two candidates will be on May 19. Analysts expect the race to be very competitive

Senate District 37

About a thousand votes separated Assemblymember Don Wagner and former Supervisor John Moorlach from a May 19 face-off. Although some mail-in ballots are yet to be counted, Moorlach is on track to capture over 50 percent of the vote. With 100 percent of precincts reporting, Moorlach has 51.4 percent to Wagner's 45.1 percent. Naz Namazi, a fellow Republican, took third with 3.5 percent.

Wagner was favored to win the Senate seat and outpaced Moorlach in fundraising and advertising heading into Tuesday. He currently represents the 68th Assembly District but will be termed out in 2016.

Moorlach is a well-known figure in Orange County politics. He served as the city's treasurer in the mid-90s and is credited as a financial hawk. He also served multiple terms on the Orange County Board of Supervisors.

The Senate seat, which covers large portions of Orange County, was vacated when Mimi Walters won her election for Congress in 2014.

Senate District 21

Republican Sharon Runner ran unopposed to represent the Senate District 21, which includes parts of Los Angeles and San Bernardino Counties. She received 24,517 votes with 100 percent of precincts partially reporting Wednesday.

Image: Jeremey Raff / KQED