Here's a fun quote from Media Matters:
Summary: On MSNBC Live, Mika Brzezinski said that Sen. John McCain "wants to eliminate the federal gas tax—that's about 20 percent of the cost." Later, Monica Novotny said McCain is "proposing suspending the federal gas tax for the summer, potentially cutting prices by nearly 20 percent."
And this would be true if in America, as on Planet Hyperion, gasoline cost about $1.00 per gallon. But of course it doesn't. What John McCain's mavericky gas-tax pander would actually do is cut gas prices by nearly 20 cents—distinct, as everybody who made it past fourth grade knows, from 20 percent—thereby saving the average American approximately very little money, while boosting his reputation as an environmentalist without actually doing anything that helps the environment.
So, a question: Is the press innumerate? Or are they just so far gone for McCain that they'll pass along pretty much any rubbish that they think makes him more appealing to voters? My answer: both.