Austin, Tex.

This was supposed to be the Tea Party’s time. The incumbent president the rebels despise so much seemed vulnerable. The Republican establishment was AWOL, leaderless or intimidated. So the angry, God-fearing, government-loathing populist insurgents rushed into the vacuum, fired up the town halls, helped put a halt to any compromising in Congress and basically commandeered the national debate.

Then, for much of this year, they dominated the auditions for a presidential challenger.

In a spectacle about as deliberative as speed-dating, candidate after candidate tried out for the role of Not Mitt Romney — including, at times, Mitt Romney. We had the Sarah Palin tease, replaced by the short-lived Michele Bachmann infatuation, after which everyone swooned, briefly, for Rick Perry. Herman Cain is having a little fling now, though even voters who like his style don’t think he can win. Rick Santorum, who is in some ways the moralizing social conscience of the Tea Party, and Ron Paul, who plays its geeky libertarian id, have settled into single digits and bit parts as debate foils. Newt Gingrich is the class cutup, blowing raspberries at journalists.

To be fair, some of this unedifying scramble can indeed be blamed on the press corps. Special props go to the hyperactive political news sites that crave a fresh narrative every 15 minutes, even if it’s a sitcom like Donald Trump. And a hat tip to Fox News, which has helped trivialize the campaign by offering a platform to one not-ready-for-prime-time Republican semi-celebrity after another. On behalf of journalism, sincerest apologies for wasting so much of your time.

But the fickleness of the G.O.P. is not entirely a media phenomenon. The latest Fox poll offered Republican voters a menu of 11 candidates and found that not only were voters scattered across the conservative landscape, but a quarter of the Tea Party adherents sampled were still “not impressed” with anyone. It’s hard to impress a movement that only knows what it is against.