CALIFORNIA'S decision to move its presidential primary to Feb. 5 not only gives the state the earliest primary in its history, it opens up the possibility that Californians will be the first voters in big numbers in the nation, beating out such traditional early-voting states as Iowa (Jan. 14), New Hampshire (Jan. 22) and South Carolina (late January).

How is this possible?

Because a growing number of absentee voters in California receive their ballots and cast their votes weeks before election day, and if this pattern is repeated next year, these voters will be making their choices as early as three weeks before the Feb. 5 primary. What's more, their choices could influence how others vote in the early states.

Absentee voting in California has surged only in the last few election cycles, a phenomenon unique among the major states because such voting has been made so easy here. Accompanying the sample ballot for an upcoming election is an application to vote absentee.

In 2006, 3.7 million California voters cast absentee ballots in the general election, nearly 42% of the total vote. According to a study by the nonpartisan California Target Book, which I co-edit, about 2.1 million of those votes were counted by county elections officials before the polls opened Nov. 7 because absentee voters mailed in their completed ballots as early as two to three weeks before the election.

The vast majority of these early voters were categorized as "permanent absentee voters." That means they automatically received a ballot in the mail after applying for one and opting to continue the practice. Overall, there were 4 million permanent absentee ballots mailed to voters in the 2006 election, up from 2.2 million in 2004. Post-election analysis of the 2006 vote showed that at least 80% of these voters, or 3.2 million, returned them.

County officials can begin processing requests for absentee ballots and mailing them to permanent absentee voters 29 days before the Feb. 5 election. That means Jan. 7, a week before the Iowa caucuses and two weeks before the New Hampshire primary.

In 2004, total combined caucus and primary turnout in these two states was 370,000. Given the 4 million permanent absentee voters in California, of which half are expected to cast an early ballot in the 2008 primary, it's not a stretch to argue that at least that many Californians will have voted, if not before Iowans caucus, certainly before New Hampshire residents go to the polls.

And, more important, a campaign's pollsters could learn the results.

In 2006, Gov. Arnold Schwarzenegger's strategists devoted considerable resources to contacting Republican permanent absentee voters and making sure they mailed in their ballots as part of a get-out-the-vote campaign.

It would not be a big step for the pollster of a presidential campaign to poll a random sample of permanent absentee voters, whose names can be obtained from mail-list vendors, on how they voted and, if the results are favorable, make them public. Campaigns make a big deal about leading in preelection polls, mainly to raise money. What's more, if a candidate could show he or she was leading in votes already cast, the effect on other voters could be significant.

Both parties' front-runners, Sen. Hillary Rodham Clinton (D-N.Y.) and Republican Rudolph Giuliani, New York's former mayor, could lose in Iowa, New Hampshire or South Carolina before what's shaping up as a national primary Feb. 5, with as many as 20 states voting that day. But Clinton and Giuliani will have the money and staff to campaign aggressively in California for its 440 Democratic and 173 Republican convention delegates, respectively, and to contact early absentee voters and urge them to return their ballots. They also could be quick to find out how those absentees voted. And you can be sure that if absentee voters are going for Clinton or Giuliani, their campaigns won't hide this from the public.

That could set up an unexpected dynamic: California absentee results influencing how voters act in other states. For instance, if 370,000 Californians cast early votes for Clinton and Giuliani, and caucus-goers in Iowa and primary voters in New Hampshire learn this, they could be influenced by the results when they vote.

Early absentee voting is likely to strengthen the front-runners, making success by an insurgent or second-tier candidate that much harder. Only well-financed candidates can effectively compete in such large states as California. They will be able to appeal to absentee voters, just as Schwarzenegger did, and thus to bank early votes and publicize them.

Four decades ago, the California primary batted cleanup in the presidential sweepstakes — its June primary decided whom the parties nominated for president. Then the Iowas and New Hampshires began playing a larger role, and by the time the primary race arrived in California, the nominees were all but officially selected. But because California's presidential primary is Feb. 5, and because it has never had the number of absentee voters that it will in 2008, the state just might play a decisive role again.