SAN DIEGO -- A judge struck down a portion of the state's recall law on Tuesday, saying voters will be allowed to cast a ballot for a potential successor to Gov. Gray Davis even if they don't vote on whether he should be recalled.

"What is at stake is the right of a voter to decide who shall succeed the governor, if recalled. Every voter, whether they voted for or against that recall, has a paramount interest in choosing the person who will govern them," wrote U.S. District Judge Barry Moskowitz.

The decision is not likely to change the timing or outcome of the Oct. 7 special election, but it should eliminate confusion that might have affected the way some voters cast ballots, an election law expert said.

Under the state law first drafted in 1911, voters could say "yes' or "no' on whether Davis, a Democrat, should be recalled.

Only if a "yes' or a "no' vote was cast could voters then choose a potential successor from a list on the same ballot. Moskowitz shot down that portion of the law.

The portion of the California Election Code in question, Section 11382, says "no vote cast in the recall election shall be counted for any candidate unless the voter also voted for or against the recall of the officer sought to be recalled.'

"The voters of California won,' said Shaun Martin, a University of San Diego School of Law professor who filed the suit with another professor. "This is just the right of every voter to vote how they choose. Yes, no or abstain.'

In Sacramento, the Secretary of State's office said it would abide by Moskowitz's ruling. The office also will advise California's 58 counties to following the judge's order when tallying ballots, spokeswoman Terri Carbaugh said in a statement.

Carbaugh said she did not expect the ruling to slow the recall process.

Deputy California Attorney General Leslie Lopez, who argued on behalf of the secretary of state that the law was constitutional, declined comment after the ruling.

Fred Woocher, an election law attorney in Santa Monica, said some voters would likely have been confused by a ballot that allowed them to pick a Davis successor if they voted "yes' or "no' on the recall, but not if they didn't vote on it.

The format might have caused some voters not to select a successor if they voted "no,' he said. Others might have voted "yes,' believing they had to in order to pick a candidate.

"It is very important because it will help remove a lot of the confusion that has been engendered by this two-part ballot,' Woocher said.

"There are definitely people for whom this would've had an impact,' he said.

Martin insisted he was not seeking to advance a particular agenda and had not consulted with politicians on either side, but that did not stop backers of the effort to recall the governor from claiming victory.

"The courts continue to go our way,' said Phil Paule, director of Rescue California Recall Gray Davis. "The other side has gone into court trying to throw a monkey wrench into the recall process. It's a victory for the process.'

Peter Ragone, a spokesman for Californians Against the Costly Recall, said the decision "only confuses an already chaotic process.'