Berman led Sherman by 17 percentage points in the redrawn district, with 58.5 percent of voters backing him in early returns.
Meanwhile, in another battle between Democratic incumbents, Rep. Janice Hahn was leading Rep. Laura Richardson with 61.8 percent of the vote to Richardson's 38.2 percent in a redrawn 44th Congressional District.
In a closer contest, Democratic Rep. Henry Waxman held a slight lead over challenger Bill Bloomfield, 51.4 percent to 48.6 percent.
The early results were based on vote-by-mail ballots received by the Los Angeles Registrar-Recorder/County Clerk, with no precinct numbers reported.
A recent round of redistricting combined with California's new top-two runoff system left candidates from the same party facing off in some colorful and contentious races.
Last year, a Citizens Redistricting Commission managed the once-a-decade task of redrawing the state's political boundaries to account for population and demographic shifts.
Voters in 2008 approved giving the authority to a commission rather than having elected officials re-draw their own district lines to avoid conflicts of interest. The commission's new districts forced some incumbents of the same party to face each other in primary elections for the new districts.
California voters also approved changing elections in 2010 to allow the top-two vote-getters in an open primary to move on to the general election. So the first time during a presidential election, voters in some districts chose between two Democrats or two Republicans.
Among the most high-profile and hotly contested was the race between Berman, D-Valley Village, and Sherman, D-Sherman Oaks, for the newly drawn 30th Congressional District, mostly in the San Fernando Valley. Sherman has served in the U.S. House since 1997, while Berman has been in Congress since 1983.
The two moderate Democrats fought a bruising campaign in order to distinguish themselves from a shared constituency. The race turned particularly ugly during a debate at Pierce College last month, when a back-and-forth turned physical as the subject turned to immigration legislation. Berman moved close to Sherman, and Sherman put his right arm around Berman's shoulder and asked, "You want to get into this?" The men separated as a sheriff's deputy moved toward them.
Richardson, D-Long Beach, and Hahn, D-San Pedro, were forced to run in a new district that includes San Pedro, Compton, Willowbrook and South Gate. Both are relatively new in Congress. Hahn was elected in a runoff in 2011 to replace retired former Rep. Jane Harman. Richardson was elected in 2007.
Richardson trailed far behind Hahn in a June primary, and her campaign was dealt a severe blow in August when the U.S. House of Representatives voted to reprimand her for violating standards of conduct. The charges included abusing her staff and obstructing an investigation into her conduct. She agreed to the penalty for the reprimand, including a $10,000 personal fine for misusing taxpayer funds.
Waxman, D-Los Angeles, represents a district stretching along the coast from Santa Monica to Malibu and up into Calabasas in the Western San Fernando Valley and saw his district changed to include the South Bay coastal communities and Rancho Palos Verdes. A member of Congress since 1975, Waxman faced a tough challenge from Bloomfield, who is listed as having no party preference.
Bloomfield has painted Waxman as an entrenched, highly liberal and partisan Democrat in a do-nothing Congress.
Los Angeles City Councilman Tony Cardenas, making a bid to become one of the first Latinos to represent the northeast San Fernando Valley in Congress, led his opponent David Hernandez with 68.8 percent of the early vote. Cardenas is running in the newly drawn 29th Congressional District, which pulled geographic areas represented by Berman and Sherman and is more than two-thirds Latino.
At least one Southern California Assembly race has drawn statewide attention.
Alarcón finished second behind Bocanegra in the June 5 primary, garnering 26.9 percent of the vote to Bocanegra's 36.2 percent. But that battle became highly charged after Alarcón and his wife were ordered last month to stand trial on perjury and voter fraud charges stemming from allegations that they did not live in a Panorama City home Alarcón claimed as his residence.
A Los Angeles Superior Court judge found there was sufficient evidence to require Alarcón to proceed to trial on 17 felony counts, including perjury by declaration, perjury in an application for a false drivers license, falsifying a declaration of candidacy and fraudulent voting.
If he maintains his solid lead, Bocanegra will take on a seat being vacated by Assemblyman Felipe Fuentes. Bocanegra is Fuentes' chief of staff.