Washington ? Some call them “the unreliables” — huge numbers of prospective voters who favor one party or the other but have a spotty record of actually showing up at the polls.

Six weeks before Election Day, both parties are mounting an unprecedented effort to get these highly prized people to cast their ballots — not on Nov. 2 but as far in advance as possible, in some cases this week.

In Arizona, singer Linda Ronstadt urges people at a rally to vote early. In Ohio, volunteers deliver an absentee request form to a homebound 85-year-old woman. In Iowa, Democrats train thousands of volunteer couriers to pick up early ballots from voters.

With 32 states, including Kansas, now offering some form of early voting, the tradition of mounting a massive get-out-the-vote drive in the week before the election has given way to a sustained six-week chase as balloting in one state after another opens for business. In a sense, it’s like the movie “Groundhog Day,” requiring the campaigns to treat every day like Election Day for more than a month.

For example, Democrat John Kerry’s trip to Iowa this week was keyed to the start of early voting there Thursday.

Iowa is a good state to illustrate the importance of the effort: In 2000, George Bush won a majority of the ballots cast on Election Day — but he lost the state to Al Gore, who had greater support among early voters.

Both Iowa and Maine, two battleground states where any registered voter can cast an early ballot, begin mailing out absentees and welcoming walk-in voters this week.

With plenty of prodding from the Bush and Kerry camps, more than 100,000 Iowa voters already have submitted absentee request forms. Some of those were turned in as far back as January, when participants in party caucuses were a captive audience for officials preaching the benefits of early voting.

In many target states the general strategy is the same: to identify unreliable votes and get them to request early ballots. The parties then can determine from election officials which voters have returned those ballots — and which should be prodded.

“You have to chase ’em to turn in their application, and then chase down their ballot,” says Jim Pederson, Democratic Party chairman in Arizona.