Obama's record in the Illinois state legislature shows his sense of bipartisanship is built on a desire to build consensus for his very Progressive goals. Rather than demonize his political opponents, he accepted their arguments at face value; he then convinced them why his goals were consistent with their principles and arguments. He did not bully, threaten, or use coercive force of any sort- he just used reason.
Damozel - fast becoming one of my favorite left-of-center bloggers - has a beautiful take on this:
If people feel that a measure that infringes or undermines their interests has been imposed on them by the opposition, they will kick back----as we saw with the Bush Administration's Republican Congress. On the other hand, if you can show them why the measure helps them, or demonstrate that there are ways to address their concerns without losing the benefit of the measure, you can get the bill passed; and once it's in effect, they can then see for themselves that the worst case scenario doesn't come into being. Which means that you're in a better position to make the next change.... This route to implementing a progressive agenda takes longer, but represents the difference between building your house on quicksand and building it on firm ground.
This is how I think Madison would have envisioned the passage of good laws. Not by creating two giant monolithic interest groups that reflexively oppose anything the other group supports. As I said earlier today, this enhances the opportunity for corrupt policy by uniting each party behind every issue that is of paramount importance to just one constituent interest group within the party. The Madisonian principle of mitigating factions no longer applies: only the monolithic faction in control of the government matters; its members need not concern themselves with being in the minority on other issues of importance to them, because they are guaranteed to be in the majority on all issues important to them.
This creates a very real problem of tyranny of the majority, except worse- it's really a tyranny of a minority of people within the most powerful political party at the time. This is one reason divided government works well- although each party's policies on a given issue are dictated by one group within that party, that group is often deterred by the fact that an opponent interest group resides in the other party, which controls another gateway to policy implementation.
But when a politician like Obama recognizes that the two parties are not really monolithic (or at least don't need to be), the problems of faction are mitigated. Coalition and consensus building through reason and persuasion become important on every issue since you implicitly realize that you are not in the majority on every issue and don't want to get bowled over on those issues where you are in the minority. As Damozel correctly points out, this strategy of consensus building by persuasion takes longer. But it also makes it more likely that the final policy is the policy most likely to succeed rather than the policy that most benefits a particularly powerful subgroup of the most powerful party.