After all this time, and despite all those warnings, the tea party's boil still has the capacity to singe -- and even shock -- the Republican Party.
The overtime primary contest for Senate in Alaska -- with tea party favorite Joe Miller up a shocking 1,700 votes pending the counting of absentee ballots -- would mark perhaps the biggest upset of the election cycle, if Sen. Lisa Murkowski, R-Alaska, goes down in defeat.
National Republicans are pulling back in their support for Murkowski in a possible legal fight, in an acknowledgement of the likelihood of a Miller victory when the votes are counted.
That contest is unlikely to change the balance of power in the Senate, since either Republican would be a heavy favorite. But a Senator Miller would join a growing cohort of Republican senators -- new tea partiers plus like-minded veterans led by Sen. Jim DeMint, R-S.C. -- who owe little or nothing to GOP leadership and the party establishment.
Before we get there, tea partiers get a few more chances to exert their influence. Little-known Republican candidates for Senate in Delaware and governor in Maryland are hoping that, like Miller, a Sarah Palin endorsement plus tea party energy is a formula for beating far better-funded and better-known establishment candidates.
Then there's the fall, when tea party action in primaries could jeopardize Republican chances for pick-ups in Senate races in Florida, Nevada, Kentucky and Colorado.
Republicans in Washington have long argued that tea party enthusiasm is an unabashed positive for them, particularly when set against President Obama's lagging popularity, and the lack of excitement among rank-and-file Democrats this year.
But the continuing impact of tea party candidacies on elections strongly suggests that this is not a political phenomenon that will work itself out with no lingering damage to the GOP.
Many tea party activists contend that their movement does not adhere to either particular party -- and it may be that it doesn't boost either party substantially.
This weekend's massive rally on the Washington Mall stands as testament to both the potential and the limits of the nascent political force.
Rallied by Glenn Beck and cheered on by Palin, the crowd massed with only an oblique alignment with the tea party movement. The rally was more about spirituality and cultural values than about the fiscal conservatism that's bound tea partiers in smaller gatherings across the country.
Moreover, the movement remains essentially leaderless. Attempts to corral its energy have run up against fierce resistance at every turn, with top-down organizing conflicting with the movement's spirit.
In the middle of so much of it is Palin, her political motives unclear, but her political celebrity unquestioned.
Backstage at the Beck-led rally yesterday, she told ABC's Christiane Amanpour that this will be a big year for "common-sense, constitutional conservatives."
"That's what Americans are ready for, that kind of change where we get back to protecting our Constitution and limiting government. That's what I think we need to see reflected here," the former Alaska governor said.
Republican leaders in Washington could look over that same gathering with optimism -- but of the guarded variety. As Team Obama knows well, change can work for or against either party.