Brad poked at something interesting in this post and if I might, I'd like to expand on it just a bit. Last year, before the Democratic presidential candidates began arguing against each other's "theories of change," environmental groups were involved in a fight of their own about a similar idea. With a narrow Democratic majority in Congress and a fiercely anti-environment president in the White House, how should they approach the climate legislation that they knew was coming down the pipeline? Greener groups took the position that the Congress should only pass a bill that would adequately address the crisis, while more establishment-oriented groups held that a bill like Lieberman-Warner should be shoved through the sausage maker and hopefully signed (though possibly vetoed) even if the end product was inadequate to the essentially scientific problem at hand. It could, after all, be strengthened in the months and years ahead.
I myself was basically torn between the two approaches, both of which have compelling pros and regrettable cons, but I ultimately stopped thinking about it when Lieberman-Warner made it through the full Senate Environment and Public Works committee--slightly improved, though still not tough enough for Greenpeace and others. Either this won't make it out of the Senate, I thought, or it'll be vetoed.
After several months of inching closer to the next presidency, though, I'm starting to think that the best course for environment-minded Democrats is patience. The worst-case scenario, after all, is if the L-W caucus finds itself lured into bad-faith negotiations with the president, who succeeds in weakening it substantially. If that happens, it passes, and he signs it, then we're stuck with some middling, difficult-to-improve climate legislation. If he vetoes it anyhow, then Senate Republicans can still use it as a sort of weak threshold during the 111th Congress.
Waiting for President McCain wouldn't be any worse than that, and moreover, a President Obama or President Clinton could use his or her early leverage to demand that the Congress either significantly strengthen Lieberman-Warner or ditch it in favor of a new bill that incorporates the most important aspects of their own climate white papers. Either way, biding time looks like the more promising way forward if the goal is to make the best-possible bill the law of the land. On the other hand, if the goal is to give John Warner a final feather in his cap...