US presidential hopefuls Hillary Clinton and John McCain hold impressive leads in the races for their parties' nominations in California just one week before the state primaries, according to a new poll released Tuesday.

The Los Angeles Times/CNN/Politico poll, conducted by Opinion Research Corp., showed that Clinton and McCain enjoy double-digit margins over their nearest rivals in California, but many prospective voters say they could still change their minds.

Clinton maintained a 49 percent to 32 percent lead over Illinois Senator Barack Obama among California Democrats, despite losing some support in key voter groups. The poll found that Democratic women continued to side with the New York senator by nearly a 2-1 margin.

The poll was conducted largely before Obama's victory Saturday in South Carolina and the subsequent high-profile endorsements of him by US Senator Edward Kennedy and his niece, Caroline Kennedy Schlossberg.

According to the Los Angeles Times, although the effect of those events was unclear, the gyrations of the presidential season had California voters uncertain of their loyalties even before the latest developments.

Among those likely to vote in the Democratic primary, 3 in 10 said they could change their minds -- including more than half of those supporting John Edwards, in third place with 11 percent of the vote.

Meanwhile, more than 4 in 10 Republicans said they could end up backing another candidate by election day on February 5, the so-called "Super Tuesday" when nearly two dozen states hold primaries or caucuses.
   
However, the poll showed McCain has vaulted ahead of three other candidates from the Republican Party with whom he shared a statistical tie for the party's nomination just two weeks ago.

The survey, which questioned 1,820 registered voters last week, also found how the quirks of California's primary could affect the vote when the results are tabulated.

About half of voters in California are expected to use mail-in ballots -- which have been available since January 7, and Clinton was romping over Obama among that group, 53 percent to 30 percent.

But among those expecting to cast ballots in a traditional precinct visit, the race was a closer 42 percent to 34 percent in Clinton's favor.

Unlike in past campaigns, when the state's delegates were largely awarded to the statewide winner, delegates this year will be allocated on both sides under formulas that are tied to the results in each congressional district.

(Xinhua News Agency January 30, 2008)