TALLAHASSEE -- One of the slickest political tricks of all time was pulled off in broad daylight this spring when the Republicans contrived to do away with next year's runoff primaries. If they don't need one, the Democrats sure do. There may be at least six plausible Democrats running for governor, not counting the usual array of nonentities filing for the fun of it. In that event, someone could be nominated with as little as 16.7 percent of the vote, which would suit Jeb Bush and the GOP just fine.

If nothing more, they get a Democratic foe who has no statewide consensus and is open to attack as a sectional or fringe candidate. What the Republicans most hope, making no secret of it, is that the Democrats will nominate their best-known potential candidate, Janet Reno, who is also their most unpopular. Reno's record as U.S. attorney general would be as much an issue as Bush's record as governor. Though she's getting plenty of applause at the moment, the risk is that many in those audiences are self-selected liberal Democrats. A Democratic poll of all voters found her unfavorable rating higher than her favorable rating, 41 percent to 35, a dreadful ratio.

Bush would also benefit from the public's inevitable concern over her Parkinson's disease. The television cameras would make that point for him. A winner-take-all primary is hugely advantageous to the best-known candidate, regardless of his or her controversiality. In the final showdown, whether in a runoff or in November, the reverse is true. While it's practically impossible for a candidate to shed disapproval points, a lesser-known candidate who hasn't made so many enemies has nowhere to go but up, which is how LeRoy Collins, Reubin Askew, Bob Graham and Lawton Chiles overcame the better-known baggage carriers who had led them in first primaries.

The Republicans running the House of Representatives did not know who might wander in to their trap, but it is looking better to them than even they could have expected. They did it under cover of the "must-pass" bill to modernize election procedures and equipment. One scandal thus begat another. The pretext was that the election supervisors needed to be rid of the runoff to finesse their absentee ballot problems, but of course it doesn't matter to the supervisors who gets nominated or elected so long as they can't be blamed for it. The Democrats let it happen. When Bill Posey, the Senate elections chairman, offered to restore the runoff in exchange for advancing the primary from September to August, no one took him up on it. It's now too late for that.

But it is not too late to add an instant runoff to the primary ballot, now that punch cards are history and every county will have sophisticated vote-counting equipment. In an instant runoff, voters mark second and third choices, which aren't counted until their first choices are out of the running. The Legislature reconvenes in January, allowing plenty of time. While costing next to nothing and adding not a day to the election schedule, it would assure Floridians a choice among candidates who represent the greatest strengths, rather than the extremes, of their parties. There can be no honest objection to that other than, perhaps, the issue of educating voters to the instant runoff, which shouldn't be hard to do.

Here's how the Center for Voting and Democracy, based in Washington under the leadership of former Rep. (and presidential candidate) John Anderson, explains it: "All the voter has to do is rank one or more candidates. It's like renting a video or picking an ice cream: What video (or flavor) do you want? That's your first choice. If they don't have that video (or flavor), what would you like? That's your second choice. If they don't have that, what's your third pick? That's all there is to it. It's as easy as 1-2-3." The entire 148-member Australian House of Representatives is elected in this fashion, which produces an eventual majority winner every time despite very crowded fields.

In Florida's case, we wouldn't necessarily need to start with an instant runoff in every race, but only in those for statewide office. For more details, including the American states and localities already using or considering this, visit the Center's Web site: www.fairvote.org . House Minority Leader Lois Frankel, who is already in the Democratic gubernatorial race, said last week the instant runoff "sounds good" to her and she'll have the bill introduced in January. The Democratic Party may back it with more than words; Bob Poe, the state chairman, says he thinks there may be legal grounds for the party to assert the right to a runoff even if the Republicans don't want one for themselves.

That is probably a long shot, and the better odds are that the Republicans would kill the bill. But they couldn't claim absentee ballots as a pretext and their motives would be laid bare. It would also dramatize to the Democrats why, for them, more is not better in the race against Bush and why the greatest service most of them could perform for their party would be to defer to the two or three who might have a fighting chance to take him out.