Political revolutions leave chaos in their wake. Republicans cannot shut down their presidential nominating contest because the party is in the midst of an upheaval wrought by the growing dominance of its right wing, its unresolved attitudes toward George W. Bush’s presidency, and the terror that the GOP rank and file has stirred among the more moderately conservative politicians who once ran things.

When Pat Buchanan ran for president in the 1990s, the conservative commentator lovingly referred to his partisans as “peasants with pitchforks.” The pitchfork brigade now enjoys more power in Republican politics than even Buchanan thought possible.

Mitt Romney is still the Republican front-runner by virtue of the delegates he relentlessly piles up. But Romney keeps failing to bring this slugfest to a close. No matter how much he panders and grovels to the party’s right, its supporters will never see him as one of their own.

One senses that the conservative ultras are resigned to having to vote for Romney in November against President Obama. They are determined not to vote for him twice, using the primaries to give voice to their hearts and their guts. They will keep signaling their refusal to surrender to the Romney machine with its torrent of nasty advertisements and its continuing education courses in delegate math designed to prove that resistance is futile.

The more they are told this, the more they want to resist.

Rick Santorum is a superb vehicle for this cry of protest. He is articulate but unpolished. He has pitifully few resources compared with the vast treasury at Romney’s disposal, but this only feeds Santorum’s David narrative against the Goliath that is Team Romney.

Santorum’s purity as a social and religious conservative is unrivaled, and his traditional family life — he’s always surrounded on primary nights by a passel of kids — contrasts nicely with Newt Gingrich’s rather messy personal history. It is no accident that, while Gingrich narrowly carried the ballots of men in Tuesday’s Alabama and Mississippi primaries, he was routed among Republican women who were decisive in Santorum’s twin triumphs. It was the conservative version of the personal being the political.

And while Republicans shout to the heavens against class warfare, they are as affected as anyone by the old Jacksonian mistrust of the privileged whose football knowledge comes not from experience or ESPN but from their friendship with the owners of NFL franchises. In Mississippi and Alabama, Romney again prevailed among those with postgraduate educations and incomes of more than $100,000 a year. He was defeated by those with less money and fewer years in school.

The revolt of the right-wing masses means that Romney stands alone as the less than ideal representative of a relatively restrained brand of conservatism. The growing might of the conservative hard core, reflected in its primary victories in 2010, led other potential establishmentarians to sit out the race in the hope that the storm will eventually pass.

But having decided to run, Romney must wage a campaign of denial. He buries his old Massachusetts self and misleads about what he once believed. He even tries to run to Santorum’s right. Recently, he denounced Santorum for voting in favor of federal support for Planned Parenthood, a group to which Romney’s family once made a donation. It is an unseemly spectacle.

Bush’s efforts to craft a “compassionate conservatism” friendlier toward those in the political middle collapsed into ruins years ago. This year’s Republican candidates almost never speak Bush’s name. It is to Santorum’s discredit that he did not dare defend his perfectly defensible vote in favor of Bush’s No Child Left Behind education program. Santorum, too, fears the pitchforks wielded by those who see any exertion of federal authority as leading down a road to serfdom.

And so it is on to Illinois, the next place Romney has to win to keep the resistance at bay. The Land of Lincoln would be a fine setting for a stand in favor of a more measured form of conservatism. But it won’t happen. Romney is anxious about the power of the Republican right in downstate Illinois — the very region that opposed Honest Abe in his celebrated Senate race 154 years ago.

Once again, Romney will take the moderates for granted, ignoring the last remnants of the old Lincoln party as he chases after an elusive right. And once again, Santorum’s battle cry will challenge conservatives to have the courage to complete the revolution they started the day Barack Obama took office.

ejdionne@washpost.com