An Aug. 26 article incorrectly said that one-third of registered voters cast ballots in the 2000 presidential election. The correct figure is two-thirds. (Published 8/27/04)

In Iowa, voters will begin casting ballots a week before the first scheduled debate between President Bush and his Democratic rival, Sen. John F. Kerry. In Arizona, campaign officials for both candidates estimate that half the state's votes will be cast before Election Day. And there will not be any polls open Nov. 2 in Oregon, because the only way to vote in that state is by mail.

These battleground states are part of a national trend that offers voters an alternative to standing in lines at the polls. Thirty states allow residents to cast their vote early, either in person or by mail, and do not require voters to provide a reason. An additional 10 states, including Maryland and Virginia, have policies that allow voters to cast absentee ballots for a variety of reasons, such as a long commute.

"A revolution has taken place," said Brian Lundy, founder of Helping Americans Vote, a group aiding businesses and trade associations in educating their employees about the new laws. "The concept of Election Day is history. Now it's just the final day to vote."

The number of states that offer no-excuse early voting has nearly tripled in the past eight years, fueled in part by the demand for election changes that followed the deadlocked 2000 presidential race. Early voting is transforming the way campaigns do business, and because this presidential race is so closely contested, it could have a significant impact on the outcome.

In some battleground states, voting will commence nearly six weeks before Election Day. For the Bush and Kerry campaigns, that means an earlier start to television, radio and mail advertising, adding to the campaign's overall cost.

"If you wait until Election Day, you've missed the first half of the vote," said Arizona Gov. Janet Napolitano (D), who credits her 2002 victory to an aggressive early vote campaign.

Supporters tout early voting as a way to reverse declining voter turnout. In 2000, only about a third of those registered to vote cast ballots, with more than 50 million opting not to exercise their constitutional right.

In states that offer early voting, the record shows that the convenience has had a modest impact on turnout. It does not turn nonregistered voters into voters, studies show. What it does do, said Michael W. Traugott, a University of Michigan political science professor who has studied the impact of early voting in Oregon, is persuade voters who might miss the odd election to vote more regularly.

Still, with the electorate evenly divided and interest high in the election, both the Bush and Kerry campaigns see early voting as a chance to bank the votes of hard-core supporters and expand their bases of support by maximizing turnout among partisans less likely to vote.

"It's extremely important, because it gives you more time to get your supporters to the polls," Kerry campaign spokeswoman Allison Dobson said.

Many states allow the campaigns to track who has requested mail-in ballots or voted early in person. By cross-referencing that list against other available information, such as party registration, phone canvassing results or even personal preferences such as magazine subscriptions, the two campaigns can target the voters most likely to support them. Then, one Bush-Cheney official said, "we will chase that vote all the way through the process."

"Early voting expands the strike zone a little bit," Bush campaign spokesman Terry Holt said.

The Kerry effort will be aided by America Coming Together, an independent group working to get out the Democratic vote. The group plans to stage marches before Election Day to polling stations that open early in key states to put "peer and community pressure" on low-propensity voters, said Patrick Gaspard, the group's national field director.

The effort is selling well among minority voters who felt disenfranchised by the 2000 election and are worried that a vote at the polls will not count, Gaspard said. "People understand that banking their vote early will help protect it."

On the other side, a coalition of business groups is trying to bank early votes by constituencies likely to vote for Bush, such as married women with children and white-collar professionals.

Census figures show that one out of every five managerial-level employees eligible to vote in 1996 did not, said William Miller, vice president and political director of the U.S. Chamber of Commerce. "My goal is to knock that number down" by informing stressed business executives about the early voting option, he said.

That could prove critical, Republican strategist Scott Reed said, because polls show "Bush is lagging" in some battleground states. Persuading more of the president's supporters to vote, he said, could offset whatever advantage the Massachusetts senator may have with less predictable independent voters.

Creativity and knowledge of the quirks in state laws can help. In the swing state of Iowa, voters begin casting ballots as many as 40 days before the election.

Last year, several churches opposed to a riverboat gambling initiative in Cedar Rapids took advantage of a little-used provision in state law that allows adult residents who can collect 100 signatures to force election officials to set up an early voting "satellite" polling station at a location of their choice, provided the location meets certain requirements.

As congregants went to cast their early votes at the churches, one preacher told them, "Let God be your conscience," recalled Linn County Election Commissioner Linda Langenberg.

The gambling initiative lost, and Langenberg is bracing for an explosion of such requests this year. Given the big Republican advantage among voters who regularly attend worship services, Langenberg was not surprised when the state GOP told her to expect petitions to set up early polling stations at area churches. She has also received requests from union halls, a furniture store, even a bar.

"Up to now, I've had an unwritten understanding with the parties that I'll set up stations that won't favor one party over the other," she said. "I don't think it's right that special interest groups can demand that a polling place be set up for their advantage."

Other critics argue that early voting undermines a sense of community and deprives voters of crucial late-breaking information about the candidates.

In 2000, for example, George W. Bush was forced to acknowledge a 1976 arrest for drunken driving five days before the election, an admission that exit polling showed cost him some votes. But in states such as Tennessee, where Bush squeaked out a victory and more than a third of the votes were cast before Election Day, some voters did not have that information when they cast their ballots.

"As much as possible, people ought to have the same information when they go to the polls," said Curtis Gans, director of the Committee for the Study of the American Electorate. "I also think going with your fellow citizens to the polling place reaffirms a sense of civic duty."

But Meredith B. Imwalle, spokeswoman for the National Association of Secretaries of State, said that view is old-fashioned. "The days of white-picket fences and going with your neighbors to the polls are gone," she said. "States are trying to make it as easy as possible in this society of two-parent working households for people to vote on their own schedule."

Oregon Deputy Secretary of State Paddy McGuire has seen another benefit -- a decline in the number of last-minute scurrilous campaign attacks. "In an 18-day Election Day period, if you launch a baseless attack early, the other side has a chance to respond, and it could backfire," he said. "And if you launch it late, if half the voters have already voted, your ability to impact the outcome of the election is substantially reduced."