The tea party movement *could* be good for urbanism. I wouldn't hold my breath waiting for the movement to jump on the repeal of the home mortgage interest deduction as a cause just yet, however. One might find a little bit more traction trying to work school choice into the forefront of the consciousness of the movement, since there is already a strain of hostility there towards the existing public school establishment. That could do a lot for urbanism, but the subsidies for suburban homebuilding and suburban (and exurban and rural) infrastructure are too popular. Indeed, I get the sense from some rural tea party activists that the main reason they want the government to save money by driving down costs elsewhere is so that it could spend the exorbitant amounts necessary to keep paved four-lane highways running through the middle of the wilderness.
Urban governments have often caused their cities self-inflicted wounds, and state and federal governments have often stacked the deck, wittingly or otherwise, against urban development. However, most of the policies on all three of those levels that really retard urban development are simply not in the tea party's crosshairs. Zoning codes, historic preservation ordinances, and other building restrictions that typically burden developers far more in urban than suburban areas are the kind of thing that libertarian wonks (e.g., Ed Glaeser) talk about, not populist firebrands. Liz Lessner is probably the one leading the charge against development-retardant parking meter policies, to the extent anyone is; if she's a tea party activist, she hides it well. And, of course, the nascent tea party was in full-throated opposition to the Columbus streetcar line.
The tea party's policy priorities may align with urbanist issues on some specific issues, but unfortunately, at least for the moment, I think that that's more by coincidence than convergence of principles.