The Tea Party movement is pretty large. Let's bear in mind that many of these people have no history of attending protests, so counting their numbers at protests isn't going to give you a good estimate.
Their movement has been having rallies all over the place, which indicates how widespread the movement has become. They had a large rally at the minor league baseball park in Kansas City, Kansas some time ago. On July 4th, there was a small demo in my neighborhood, which is completely weird given that my location in the burbs never sees any kind of protest.
I've been very concerned with Glenn Beck up until his rally this weekend. Now I'm less concerned and think the way to dilute his power is to not give him any attention. He's dangerous in that he spreads some idiotic ideas among a limited segment of the population. Trying to interact with these loyal fans is becoming impossible, which I think will lead to their marginalization.
Beck's rally, if you look at it from the perspective of an organizer of protests, was a tremendous bust.
Especially by Washington, DC protest standards.
Glenn Beck had around six months of planning an promotion to organize this rally. He has popular radio and TV shows. His rally had lots of media attention in the months leading up to it. His followers are the type to do whatever the guy tells them to do. He's also put himself in front of a significant grassroots movement that is royally pissed at "Washington" right now. And his fans are mostly middle class, so they have the time and means to travel to a rally.
Any union or anti-war coalition organizer would love to have these signs aligned for a national rally on the Mall. If these factors were playing into a national anti-war protest, the turnout would have been at least 300,000. As much as I dislike ANSWER, they could have turned out a much larger mobilization with far fewer resources. I've been the primary organizer in national protests that had few resources and turned out lots of people. Even our anti-globalization protest scheduled for late September 2001 was supposed to be huge, 100,000 by police estimates a month before the event (which was canceled because of 9/11).
As far as the concern that this movement will aid the Republicans in November, you will get no sympathy from most people. The Republicans are going to win back the House simply because that how the U.S. political system works. When people are mad about something like the economy, they punish the party currently in power. The Republicans will get to enjoy their majority for a short time, since people will turn against them once the Great Recession drags on for more years.
More and more people are finally understanding that there is no difference between the parties. About time!
Chuck