I think the nay voters on cloture for the Ledbetter Fair Pay Act make a good list. These are the folks who in all likelihood are entirely unreachable by Barack Obama on most votes, short of directly bribing their constituents. Well, okay, it's not a perfect list; Dick Lugar voted "Nay", but he's almost certain to vote with the President on foreign policy and even a decent number of economic matters, especially when it comes to the auto sector. And I doubt Bob Corker, who voted "Aye", is going to be voting for much of Barack Obama's economic policy (some Southern Republicans keep at least modestly good relationships with trial lawyers, who tend to be very powerful in Southern States for a variety of historical reasons). But it is a good starting point. The cloture vote could not get 80 votes, even if all three absent Senators, including Jim Bunning (R-KY), had voted for it.
The punchline, which I think Team Obama seems to be understanding, is that why there may be broad bipartisan intellectual support for much of the Administration's agenda, that's not always going to translate into broad political support. Every economist worth his or her weight in dung realizes we need a substantial increase in government spending, but that's not going to convince David Vitter of anything unless they ... well, I'll let you use your imagination on that one. Thus 80-20 votes just won't be in the cards, meaning Obama needs to sway people like George Voinovich and Chuck Grassley, not Pete Sessions and John Cornyn.