Three key Assembly races to watch in Tuesday’s primary

Today’s primary is brimming with Assembly races featuring intra-party squabbles, torrents of outside money and general election previews. Having trouble keeping track? Here’s a guide to the top three Assembly races to keep an eye on today.

AD 16

This Bay Area rumble between Democrats Steve Glazer and Tim Sbranti has attracted millions of dollars in outside spending -- far more than any other legislative race.

Business groups, such as the California Realtors Assn. and the Chamber of Commerce, are backing Glazer, an Orinda city councilman and former advisor to Gov. Jerry Brown. Glazer has close ties with the business community, having served as a political consultant to JobsPAC, a Chamber political committee in 2012.

That 2012 campaign work -- in which Glazer worked to defeat labor-backed Democrats -- earned him the ire of labor groups. The antagonism has only deepened with Glazer’s call to ban transit strikes, after labor discord at Bay Area Rapid Transit, the region’s commuter rail system, led to two strikes last year.

Labor groups have lined up behind Tim Sbranti, mayor of Dublin, an East Bay suburb.

Catharine Baker, a Republican, is also vying for the seat, which is currently held by Assemblywoman Joan Buchanan (D-Alamo). Buchanan will be termed out at the end of this year.

AD 44

Democrats see a pick-up opportunity in this Ventura County seat, currently held by Assemblyman Jeff Gorell (R-Camarillo), who is running for Congress.

Once a solid Republican district, Democrats now have a narrow upper hand in registration: 38% to 35%, whith nearly 20% of voters stating no party preference.

The sole Democratic candidate is Jacqui Irwin, a Thousand Oaks city councilwoman, who is expected to consolidate Democratic votes and secure a spot in the top two.

The most closely watched battle Tuesday, however, will be between GOP contenders Mario de la Piedra, a businessman, and Rob McCoy, a pastor in Thousand Oaks.

Business groups, along with Republican mega-donor Charles T. Munger Jr., have spent more than $700,000 to boost De la Piedra and oppose McCoy, whom they fear could be too conservative to win this swing district in November.

AD 65

Spoiler alert: We already know who will be the top two candidates after today’s vote, because there are just two candidates running. Nevertheless, this Orange County contest will be closely watched as a preview to a key general election battle.

Assemblywoman Sharon Quirk-Silva (D-Fullerton), the incumbent, won an upset victory over sitting Republican Assemblyman Chris Norby in 2012. Now, she’s looking to fend off a challenge from Young Kim, a Republican who used to be a staffer for Rep. Ed Royce (R-Fullerton).

The district is almost evenly split between Democrats and Republicans -- 37% to 35% -- and 23% of registered voters designated no party preference.

Both candidates have posted strong fundraising numbers: Quirk-Silva reported having slightly more than $500,000 in the bank as of May 17, while Kim had about $470,000 cash on hand.

In a clear sign of how important the race is for Assembly Democrats’ hopes to retain their supermajority, Speaker Toni Atkins (D-San Diego) will be appearing at a Quirk-Silva campaign event Tuesday afternoon.