Jonathan Chait observes that Jennifer Rubin, while trying to prove that the Tea Party represents the views of the "majority of Americans," quotes an article that cites a study showing that they "command the active allegiance of between 13 percent and 15 percent of the electorate," which is you know, not a majority. They're just under the number of people who believe in aliens, ghosts, witches, astrology, and nowhere near as numerous as the number of people who think marijuana should be legalized.
You don't have to represent the majority of Americans to have a substantial impact on elections, but that's not what Rubin was arguing. Saying "the Tea Party's views are shared by large numbers of influential political elites with the ability to substantially impact the outcomes of elections and policy disputes" doesn't quite have the same populist pizazz.