The overall Republican stance on climate change(I guess I have to point out this applies to the party generally, not every single person who identifies as "Republican" individually) currently is that it is 1. not real, 2. not caused by man or 3. not harmful. And if you believe any one of those three, then the $7500 tax credit(plus $2,500 rebate in CA) for buying a car that doesn't produce CO2, is absurdly unfair, so some resentment would be called for. I know I'd get pissed off if, say, anybody who bought a $100k+ gas-powered sports car got a check from the government for $10k because, say, someone thought the increased acceleration caused the earth to rotate slightly faster, reducing warming.