Senator Murkowski's ostensible reason for stripping EPA of its regulatory authority was that the CAA is an inferior vehicle for regulating GHGs. In this, she is entirely correct. Special legislation regulating GHG emission would be vastly preferable to EPA regulation under the CAA, which is not well-designed to deal with the special problems posed by GHGs (witness the various, possibly illegal, machinations in EPA's final proposed GHG rule to bend the CAA to fit GHGs). However, beyond Senator Murkowski's ostensible reason for removing EPA authority to regulate GHGs lies another, more devious purpose, which is to prevent any regulation of GHGs. If her proposed legislation had passed, prospects for the Kerry-Lieberman bill would have been greatly reduced. Without the overhanging threat of EPA regulation, it is doubtful that any substantive climate bill could obtain the 60 votes necessary for cloture in the Senate. Thus, defeat of the Murkowski bill was a critical prerequisite for passage of Kerry-Lieberman.
But what does the 53-47 vote tell us about the likelihood of passage for a real climate bill? Ezra Klein, writing here in the Washington Post, thinks that the vote cannot be good news for climate legislation. After all, 6 Democrats, including Blanche Lincoln, defected, voting to support Murkowski's bill. However, I am at least somewhat less pessimistic. For one thing, it appears that proponents only need 6 more votes for cloture - it seems highly unlikely that anyone who voted against Murkowski's bill would vote against Kerry-Lieberman. Meanwhile, it is at least possible that some who voted in favor of the Murkowski bill might now favor Kerry-Lieberman to avoid presumably more onerous and costly EPA regulation under the CAA. Indeed, some who voted for the Murkowski bill might have done so not because they support it but for political cover, knowing that the bill was going to fail. Now, they can tell their constituents that they must support Kerry-Lieberman to avoid the prospect of regulation by the dreaded EPA.