LOS ANGELES -- In a statewide primary that tested incumbent strength after election reforms, voters largely stuck with established names Tuesday, setting up several contests in which members of the same party will face off this fall. They also shortened the tenure of state lawmakers in Sacramento and put limits on public pensions in two of California's largest cities.

A contentious ballot proposal to add a $1-a-pack tax on cigarettes to fund cancer research remained too close to call after a $65 million spending spree by opponents and supporters. Opposition to the hike held a roughly 64,000-vote lead out of more than 3.8 million cast, but many votes remained to be counted Wednesday.

U.S. Sen. Dianne Feinstein, the 78-year-old incumbent Democrat, easily advanced to the November ballot in her quest to for a fifth term, where she will face Republican autism activist Elizabeth Emken.

Nearly two-thirds of voters approved an initiative to alter the state's 22-year-old term limits law, cutting the possible tenure of state legislators from 14 years to 12 years, but allowing them to serve all that time in one house. In San Diego and San Jose, voters overwhelmingly approved measures to cut retirement benefits for government workers in contests closely watched as states and cities throughout the country struggle with public employee pension obligations.

The primary was the first statewide use of a top-two voting system and legislative and congressional districts

that were drawn for the first time by an independent citizens panel.

The changes produced several legislative and congressional contests where candidates from the same party will meet again in November, but early returns showed most of the closely watched independent candidates were not faring well, including Chad Condit, the son of former Rep. Gary Condit, who had hoped to challenge for the Central Valley seat his father once held.

Two long-serving Democrats, Reps. Howard Berman and Brad Sherman, advanced to a November showdown in a bitterly contested San Fernando Valley area district that was a marquee matchup among California's congressional races.

Two Democrats also appeared headed for a same-party showdown in the Central Coast's 13th Senate District, where Assemblyman Jerry Hill of San Mateo faced former Assemblywoman Sally Lieber of Redwood.

Democrats hope to pick up as many as six seats in California's 53 congressional districts and have been working to register more voters in traditionally Republican-leaning areas of the Central Valley and the Inland Empire region of Southern California.

In San Diego, four well-known candidates were running for a spot in the fall runoff which will feature the top two finishers.

Republican Carl DeMaio, a city councilman, led with nearly a third of the vote, followed by U.S. Rep. Bob Filner, the lone Democrat in the race. Assemblyman Nathan Fletcher, who switched his affiliation from GOP to independent during the race, was in third place.

In a state where voters usually face a long list of ballot measures, only two initiatives qualified before the Legislature passed a law moving all future measures to general elections.

Voters approved Proposition 28, the term limits measure that supporters said would establish consistency and reduce the influence of lobbyists. Opponents said the initiative was misleading because few lawmakers actually serve 14 years under the current system, which allows six years in the Assembly and eight years in the Senate.

Voters also were asked whether to add a $1-a-pack tax to cigarettes to help fund cancer research and anti-smoking campaigns in an expensive ballot fight that saw opponents, including tobacco companies, pour more than $47 million into their campaign. Supporters raised nearly $18 million for the measure, which was backed by cycling legend and cancer survivor Lance Armstrong.

The anti-tax ad campaign had an impact, and support for the hike eroded as primary day drew near. With all precincts reporting votes, opponents led by a little more than 1 percent but an unknown number of late-arriving early and absentee votes remained uncounted Wednesday, making the race too close to call.

The pension proposals drew national attention as possible bellwethers of anti-union sentiment. State GOP Chairman Tom Del Beccaro said voters have an appetite for government reform.

”Perhaps most interesting is that this wasn't a partisan cry for reform; even in a large city such as San Jose which has heavy Democrat registration, taxpayers stood up against union bosses and big government,” Del Beccaro said in a statement.

Advocates for public employee unions said they were outspent 8-to-1 and that the pension rollbacks will be ominous for workers.

The change approved by San Diego voters imposes a six-year freeze on pay levels used to determine pension benefits unless a two-thirds majority of the city council votes to override it. It also will put new hires, except for police officers, into 401(k)-style plans.

Under San Jose's Measure B, current workers would have to pay up to 16 percent of their salaries to keep their retirement plan or accept more modest benefits. New hires would get less generous benefits.

Election officials reported few problems at the polls and traffic was slow throughout the day, with some pundits predicting voter turnout could be as low as 25 percent, which would be a record low for a presidential primary.

”It looks abysmal,” said Contra Costa Registrar of Voters Steve Weir. “It looks like this could be an almost all mail-in ballot elections. It's seemingly that bad.”

Weir estimated that about 20 percent of ballots might not be processed Tuesday, which could leave many candidates waiting to find out Wednesday if they made the November runoff.