After releasing an ad earlier this week that contained debunked lies about offshore drilling and gas prices, John McCain unveiled a new ad today, "Dome," that hits on classic conservative fears of "massive government,&quot and both "painful" and "skyrocketing" taxes. The ad’s voiceover specifically stokes fears of "skyrocketing taxes on life savings, electricity, and home heating oil."

This resurrects an old, discredited claim made this summer in the original "Celeb" ad. (Remember when we thought that was as low as the McCain camp could go?) It has been thoroughly debunked by

McCain’s new ad claims that Obama "says he’ll raise taxes on electricity." That’s false. Obama says no such thing.

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McCain relies on a single quote from Obama who once – and only once so far as we can find – suggested taxing "dirty energy," including coal and natural gas. That was in response to a reporter’s suggestion that a tax on wind power could fund education. Obama isn’t proposing any new tax on electricity or "dirty energy" as part of his platform, and he never has.

It’s true that a coal/gas tax would raise electric rates, but so would a cap-and-trade program to restrict carbon emissions. Cap-and-trade is an idea that both McCain and Obama support, in different forms. Neither candidate characterizes cap-and-trade as a "tax."

It’s interesting that they throw in the claim about home heating oil to make it fresh as colder temperatures (and skyrocketing bills for home heating) draw near. Since 2005, McCain has voted against funding for the Low Income Heating Assistance Program (LIHEAP) at least five times. In fact, just before the August recess his Republican colleagues in the Senate blocked attempts to double funding for the program.

In case you’ve forgotten what it was like when the McCain campaign was only petty, not petty, dishonest, and nasty, here’s the ad from this summer:

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