While Democrats still have the power and the momentum in the health care debate, and the odds are in favor of at least some form of legislation getting passed, there’s also an increasing possibility that this whole thing can come apart, and I think a good parallel is the Bush administration’s push for comprehensive immigration reform.

Obviously, there are significant differences in the circumstances, not the least of which is President Obama’s clout. But the dynamics are similar in this sense. During the immigration debate, you had Democrats in Congress who weren’t eager to give President Bush a legislative accomplishment on a significant issue and then the conservative base was angry about what it saw as a Republican sell-out on an amnesty bill. Eventually, everything unraveled.

As I reported last week, we’ve moved beyond the happy talk stage of the health care debate and some of the familiar fault lines are beginning to form. The American Medical Association has come out against a government-run plan (at least in its pure form), business groups are worried about the employer mandate, and Republicans are starting to raise a fuss about how Democrats are trying to ram through legislation. So, if Democrats want to pass something, it’s quite likely at this point that they’ll have to drop the government-run plan (which Democrat Sen. Kent Conrad, chairman of the Budget Committee, said they don’t have the votes to pass). However, from the mindset of liberal activists, including those who plan to spend $82 million to push for health care legislation, if Congress ditches the government plan, they’ll be left with legislation that provides subsidies for individuals to purchase private insurance. To liberals, this isn’t real reform, but merely pumping more money into a broken system. If Democrats try to reassure the base and urge liberals to accept the best deal that can pass, those lawmakers will sound a lot like the Republicans who tried to convince the conservative base that the comprehensive immigration reform didn’t represent amnesty and would be a step forward on border security and enforcement. So, if you combine more or less unified Republican opposition with an uprising among the liberal base over a compromise on the government plan, you begin to see how this health care push can explode before it even comes to a vote.