Watching John McCain and Barack Obama's dueling energy ads (below) back to back really highlights the precarious balancing act facing the Republican nominee. To an extraordinary degree, both ads are pushing the same message: Our guy has new, better approaches to energy than the Bush administration, and the other guy is just a partisan hack.

But for obvious reasons the McCain ad (which was paid for by the RNC) has to make the first point very gingerly and obliquely, stating merely "He's pushing his own party to face climate change." Obama's ad, by contrast, is direct and emphatic, offering footage of McCain and Bush hugging (expect to see a lot of this over the next few months) while the announcer intones, "McCain and Bush support a drilling plan that won't produce a drop of oil for seven years. McCain will give more tax breaks to Big Oil." 

On the partisan hack charge, too, the contrast plays against McCain. His ad ends with the line "Barack Obama, just the party line," while onscreen text cites "97% Party Line Voting, 2007." But again, Obama trumps him with announcer and text both emphasizing that McCain has "voted with Bush 95 percent of the time." It may not be a great thing to be seen as a party-line Democrat. But these days it's a hell of a lot better than being seen as a party-line Bushie.

Finally, there's an unresolved tension in the McCain ad, and in his campaign generally: He needs simultaneously to draw contrasts between himself and Bush and between himself and Obama, which can be a very delicate task. (If he disagrees with the former about climate change, doesn't that imply he agrees with the latter?) McCain may ultimately be able to resolve this conflict somewhat by triangulating against his party more explicitly (though he probably won't be able to expect the RNC to foot the bill for it). But triangulation of course carries its own risk of further alienating an already suspicious GOP base.

Obama, meanwhile, faces no such tension. His case is straightforward: Bush has been bad; McCain offers more of the same; vote for me instead. In a political environment eager for "change," this is going to be a hard message to overcome.

The McCain ad:

 

The Obama ad:

 

--Christopher Orr