Bridgett Wagner, director of coalition relations at the conservative Heritage Foundation, sees a possible reprise of the tax revolt of the 1970s and '80s, when a California movement to slash and cap property taxes led to successful ballot measures from the West Coast to Michigan and Massachusetts.
"These movements in the past have shown that when people have finally had enough, even the politicians at some point have to listen," says Wagner, calling it a "bottom-up" phenomenon.
Word spreads on Internet
The Information Age has given people the ability to network as never before, she says. In that sense, the Tea Party movement resembles the early days of MoveOn.org, which began in 1998 as a small, tech-savvy liberal group and became a behemoth in Internet fundraising and rallying.
"They're catching up on the tools," says Ilyse Hogue, MoveOn.org's spokeswoman.
Hogue was dismissive of the several hundred events the Tea Party organizers plan for Wednesday, saying her group routinely mobilizes many more.
Nevertheless, Jenny Beth Martin, a former paid consultant for local Republican candidates, says the strength of the Tea Party movement is the emergence of people not known for street action.
"It's not your hippie protesters," she says. "It's people who are working hard for their families and they don't want their money taken away from them to be given to people who aren't working hard."
Meckler agrees. He says, "They're supposed to energize a group of new activists, show them there are people much like themselves."
Dawn Wildman of San Diego, who is organizing four tea parties, says lawmakers should not be dismissive.
"We're seeing how you vote," she says. "You're not paying attention to your constituency. We put you there, and we can take you out."