What is the Tea Party? Many have tried to answer that question ever since CNBC's Rick Santelli first launched the backlash with his trading-floor rant against the poor.
Democratic operatives, for instance, say the Tea Party is merely a Republican Party facade. As proof, they point to GOP-linked corporate groups' involvement in Tea Party events, and cite the absence of Tea Party deficit and bailout protests during George W. Bush's presidency.
Social scientists, meanwhile, suggest that the Tea Party is not the entire Republican apparatus, but specifically the extreme conservative edge of the GOP. The data add credence to that argument: As the Public Religion Research Institute and the University of Washington report, Tea Party followers are disproportionately part of the Christian right and are more racially resentful than the general public.
For their part, Tea Party activists brush off these pesky facts with nostalgic paeans about the Constitution and indignant bromides against partisanship.
"Although we are conservative in political philosophy, we are nonpartisan in approach," insisted a Tea Party leader in a typical platitude. "Both parties need to rededicate themselves to the principles of our Founding Fathers.'"
Thus, with both sides at loggerheads, the only way to objectively define the Tea Party is to find a test case. And as I say in my new newspaper column, thanks to Wisconsin's Senate race, we have exactly that.