Michael Gerson

WASHINGTON -- Following the primary season, the position of the Republican Party is strong but precarious, like a bodybuilder on a tightrope. Republicans benefit from tea party momentum. They suffer from tea party victories. As part of a political coalition, the tea party movement empowers. As the dominant actor, it alienates.

The problem for Republicans: They have no idea at what level the influence of the tea party movement will crest.

Delaware's Republican Senate primary defined one possible future. Voters elevated ideological purity above every other political value, including probity, relevant experience and electability. In the process, Republicans wasted an unusual opportunity to win a Senate seat in a heavily Democratic state. One poll reports that just 31 percent of Delaware voters believe Republican nominee Christine O'Donnell is fit to hold public office.

But the primary season told other stories. Sen. John McCain's trouncing of J.D. Hayworth showed that the tea party label does not guarantee success for buffoonish candidates. In a number of states, mainstream conservatives turned aside tea party challenges and are now propelled by political winds that once threatened to capsize their candidacies. One tea party hero -- Marco Rubio -- has turned out to be a strong candidate and likely Republican star.

So the picture is mixed. Who would have thought, on election night 2008, that within two years the most potent force in American politics would be a grass-roots conservative movement that is likely to help return Republican control of the House of Representatives? But particularly in smaller Republican electorates -- Delaware's 60,000 Republican primary voters or the few thousand Republican delegates who sent Utah Sen. Bob Bennett into retirement -- intensity can overwhelm judgment. As a rule, the smaller the Republican electorate, the larger the tea party influence. The larger the electorate, the more off-putting that influence becomes.

Republican Senate prospects illustrate the challenge. Without the broad backlash to the Obama agenda channeled by the tea party, Republican control of the Senate would be inconceivable. Without the primary victories of tea party candidates in Nevada and Delaware, that control would be more likely. And some tea party activists seem content with this state of affairs, arguing that an unspoiled minority is preferable to a majority held hostage to its most liberal members. "We need people up here to understand we've got to get back to limited government," says Sen. Jim DeMint, R-S.C., who endorsed O'Donnell, "and we can't afford to have other Republicans who don't get that message."

Michael Gerson

Michael Gerson writes a twice-weekly column for The Post on issues that include politics, global health, development, religion and foreign policy. Michael Gerson is the author of the book "Heroic Conservatism" and a contributor to Newsweek magazine.
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