But Tea Partiers insist that they are not beholden to the GOP and warn that Republican candidates counting on an endorsement from them in November may well be disappointed.
Interviews with Tea Partiers across the country paint a picture of a genuine, amorphous, conservative grassroots movement united by three core principles: constitutionally limited government, free market ideology and low taxes. The American Constitution is a rallying cry and many now dub themselves "constitutional conservatives."
They are angry not just at what they describe as the socialist policies of U.S. President Barack Obama. They also feel Republican politicians have betrayed the party's ideals. For many in the movement, purging the party of moderate Republicans is a major goal.
"I used to be a dyed-in-the-wool Republican. Now if we have a Republican lined up to come to our meetings, I don't even want to go," said Nate Friedl, 41, a member of the Rock River Patriots, a Tea Party group in southern Wisconsin.
Following a first year marked by protests, the movement is evolving. The political novices of a year ago are forming coalitions and learning how to change things from the ground up.
After rallying against government bailouts and Obama's healthcare reforms, as well as mobilizing the vote for key electoral races such as Republican Scott Brown's victory in Massachusetts in January, many Tea Partiers feel empowered.