Don't be surprised if you haven't heard about this silent sea change. Unlike Democrats, who often seem more like a gaggle of squabbling special-interest groups than a political party, we Republicans don't take kindly to those who break ranks.

Over the years, this rather iron-fisted party discipline has borne valuable fruit, including the takeover of both chambers of Congress, the White House and a slew of state capitals. But it has also resulted in a Republican propensity to push to the right of the next guy and to toe the party line, lest you be branded ''a squish'' or a RINO -- Republican In Name Only. Dissension from basic party norms -- let alone party leaders -- is tantamount to heresy, so dissenters tend to keep mum.

Those propensities have made what I'm hearing from some fellow GOP-ers intriguing: They will not vote for Bush in November.

Perhaps they think that I'm a sympathetic ear. For two years, Bush has become an increasingly irritating burr under my own libertarian-leaning Republican saddle.

To an ardent believer in free trade, sacrosanct civil liberties, fiscal prudence, government-free bedrooms and avoidance of unnecessary foreign entanglements, Bush's reign has been literally one disappointment after another.

The number of e-mail screeds I receive calling me part of ''the liberal media Bush-bashers'' after I've disagreed with Bush's stance on any of those policies merely reinforces why dissident Republicans rarely open their mouths. There is always a price to pay.

But some dissenters are beginning to quietly stir. My electronic inbox, a window through which the breeze of public opinion constantly blows, has lately been filled with missives from fellow party members loath to cast another ballot for Bush.

Why? ''Because I don't trust him to be honest,'' says a federal law-enforcement veteran who always has voted Republican.

``I feel the president is arrogant and the administration smug, and I wonder what the freedom of speech is worth in an administration that personally attacks people who speak the truth.''

Another GOP-er, a ''social conservative,'' writes that his White House dissatisfaction 'started when Bush stated that the campaign-finance `reform' bill he was about to sign 'is probably unconstitutional' -- and then signed it anyway. That's dereliction of duty.''

A reader from Mobile, Ala., writes: ''I voted for Republicans since Reagan, but I'm giving serious consideration to voting for a Kerry-Edwards ticket.'' A Florida reader says, ``I changed my registration the day Bush invaded Iraq.''

As for whom they'll vote this fall, many are flummoxed. A few say Kerry, but others, spooked by Kerry's liberalism, say that they'll just stay home. One reader thinks that he may ``write in Alan Keyes.''

''My friends tell me that I'm abandoning my party in its hour of need,'' he writes. ``I point out that my party abandoned me first.''

Are these dissenters a majority of Republicans? Certainly not. But the coming election is forecast to be neck and neck, with gadfly Ralph Nader fuzzing the picture. Democrats -- highly motivated to oust Bush -- are expected to hit the polls in droves. Even a small number of Republicans who choose to sit on their hands could swing the race.

Meanwhile, the Pitcairn Island of November is looming into view, and the window of opportunity is closing. But there's no indication that the captain will alter course even one degree.

Bronwyn Lance Chester is a columnist for The Virginian-Pilot in Norfolk

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