Measuring the size and impact of the Tea Party has been an ongoing project ever since the movement began in early 2009. What we’ve learned is they’re mostly white, male, Americans older than 45 with higher-than-average income—that is, not much different from the Republican Party.

What hasn’t been established is how much of a difference the Tea Party can make in the 2010 election. Are the various groups going to mobilize huge numbers of conservatives, thus earning the right to claim they “won” the election for the GOP? Or is “Tea Party” just useful shorthand for generalized conservative opposition to President Obama, without much organizational acumen?

We won’t know for sure until after Election Day. But a survey of Tea Party organizations published on Sunday in the Washington Post may give us a hint.

Tea Party leaders have always emphasized the organization’s disorganization. At a rally last year, Tea Party Patriots co-founder Mark Meckler told me to read The Starfish and the Spider, a business book about leaderless organizations. There are two kinds of companies, the book posits: “Spiders” operate with a central leadership, a head that tells the legs what to do. “Starfish” have no central authority—each leg operates on its own. When you hit a spider on the head, it dies. But when you cut off a piece of a starfish, that piece grows into another starfish. (At least among some species.) The Tea Party, says Meckler, is a starfish.

The new Post survey suggests a better animal metaphor might be a sloth. The movement appears to be a lot smaller than its spokespeople claim. Tea Party Patriots keeps a list of more than 2,300 local groups. But the Post was only able to verify and reach 647 of them. (A group could have one member or thousands.) Of those groups, only 29 percent were doing any campaigning. And within that group, only two thirds are doing get-out-the-vote efforts, just more than half are sending letters or e-mails, and less than half are making phone calls. That’s about 84 groups in the whole country working the phones.

That may be enough to swing some tight elections. But it’s hardly the tidal wave of enthusiasm that Tea Party leaders and the Republicans who depend on them are hoping for.

Which raises the question: Could a centralized Tea Party do a better job getting candidates elected than a diffuse mass? The Tea Party’s greatest hits have all benefited from central organization. Glenn Beck and the conservative group FreedomWorks helped gather the masses for the 9/12 rally on the National Mall. Rep. Michele Bachmann organized a protest in August. The National Tea Party Convention was held in Nashville last February by a top-down group called Tea Party Nation.

Part of the problem may be that not all Tea Party groups want to get involved in elections. Meckler, for example, hasn’t endorsed any candidates. Another Tea Party Patriots organizer, Jenny Beth Martin, emphasized education over electioneering in an interview with National Journal in September. “If you just tell people to vote but you don’t talk about the underlying principles, you just have to do it again and again and again, in every election,” she said. It’s also possible that many Tea Partiers are GOTV-ing through other, non-Tea Party organizations.

Adam Brandon, a spokesman for FreedomWorks, argues that the Tea Party’s decentralization is an asset, not a liability. Whereas a hierarchical organization needs to appoint a new representative every time it expands, FreedomWorks connects with existing local Tea Party organizations. “This has given us flexibility to go everywhere,” says Brandon. There’s also evidence that the Tea Party movement has attracted donations it wouldn’t otherwise have gotten if it weren’t so decentralized.

Brandon disputes the idea that not many Tea Partiers are getting out the vote. He cited a CNN pollthat said one in 10 Americans has attended a Tea Party event or given money. “If 30 percent of this group is active, that’s a massive army,” he says.

To say Tea Partiers won’t get out the vote is not to say Tea Partiers won’t vote. If the New York Times and Washington Post surveys tell us anything, it’s that they’re more enthusiastic and politically engaged than most voters and therefore more likely to vote. What’s still unclear is whether they can convince less enthusiastic people to join them.

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