San Rafael Councilman Marc Levine took an early lead Tuesday night over incumbent Assemblyman Michael Allen in their battle for the 10th Assembly District seat.

With all precincts in, Levine held 50.6 percent of the votes to Allen's 49.4 percent.

"I'm cautiously optimistic about the outcome tonight," Levine said from his campaign party at Aurora Art Studios in San Rafael.

The two Democrats were vying to represent voters in a newly created district that spans Marin County, part of Santa Rosa and portions of western and southern Sonoma County.

The pair earned the right to compete for the district seat under California's new top-two primary system. The race gained attention in part because it was one of about two dozen in the state pitting members of the same party against one another in the general election.

"This is not so much about Levine, so much as it is about challengers wanting to take on the Democratic establishment in new districts," David McCuan, a political scientist at Sonoma State University, said Tuesday night before the polls closed in California.

Allen did not immediately return a message seeking comment Tuesday.

A former union leader who rose quickly through the ranks of power in his first Assembly term to become assistant majority floor leader, Allen was considered by political observers as the front-runner in the race with Levine, who is in his first term as a San Rafael city councilman.

Allen, who was elected to represent the 7th Assembly District, rented an apartment in San Rafael to establish residency within the new district.

Allen was on target to spend nearly $1 million in his bid, outspending Levine nearly 3-1. In addition, independent expenditure committees poured in about $700,000 to help Allen win. Levine also received a boost of $250,0000 from two independent expenditure committees.

"I don't think anyone believed we would be this competitive, but I'm proud we've given the voters of Sonoma and Marin (counties) a choice," Levine said.

In other state legislative races featuring North Coast candidates, Democratic incumbents appeared to be holding on to early leads.

In the 2nd Assembly District race, incumbent Wes Chesbro of Arcata held a 62.5 percent to 37.5percent advantage over Guerneville contractor Tom Lynch in early returns Tuesday.

In the 4th Assembly District race, which covers parts of Rohnert Park and the Sonoma Valley, Assemblywoman Mariko Yamada, D-Davis, held a 60percent to 40 percent lead over her Republican challenger, John Munn, also from Davis.

For state Sen. Lois Wolk, D-Davis, there was no suspense Tuesday night, as she ran unopposed in the new 3rd Senate District, which includes Rohnert Park, Cotati, Petaluma and Sonoma.

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