The thing is, the reverse isn't true. I really don't see liberals supporting or opposing things because they imagine it'll piss off conservatives. Oh, sure, we all have a good laugh when Rusty freaks out about something, but I don't think any of us ever think,
"Increased MPG standards will sure piss off Limbaugh! Let's vote for that!"
It's somewhat unrelated, but I'm reminded of when the Last Honest Man In Washington, Joe Lieberman, briefly floated Medicare buy-in at 55 as a kind of compromise for the public option in the ACA. I pleaded with everyone I knew to STFU about it, because of course liberals would have taken that deal. I knew that the instant the greatest man who ever lived got wind of the fact that liberals would actually love that deal he'd back off supporting it, because liberals. And he did.