Benen provides some context…

The first major general-election “contrast” ad from the Obama campaign emphasized a fairly straightforward tagline: “After one president in the pocket of big oil, we can’t afford another.”

As if on cue, we’re learning quite a bit about John McCain’s generous benefactors from the oil industry.

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To be sure, if — and at this point, it’s only an “if” — Hess played fast and loose with campaign finance law to “help” lower-level employees back the candidate willing to do the oil industry’s bidding from the White House, it doesn’t necessarily mean McCain’s campaign broke the law. It just means it took some legally dubious contributions.

It would, however, reinforce the notion that Big Oil has picked their guy in this presidential race, and are attempting to buy John McCain. If Obama’s message is that we can’t afford another president in Big Oil’s back pocket, suspicious oil-industry fundraising only helps make the argument more compelling.