Brendan Nyhan flags this preposterous lede:

3 Candidates With 3 Financial Plans, but One Deficit

The Republican and Democratic presidential candidates differ strikingly in their approaches to taxes and spending, but their fiscal plans have at least one thing in common: each could significantly swell the budget deficit and increase the national debt by trillions of dollars, according to tax and budget experts.

Brendan thinks the problem here is a tendency toward false equivalence. I'd say it may be simple innumeracy. Later in the article we find out that McCain's proposals "if enacted as proposed, would add at least $5.7 trillion to the national debt over the next decade." Conversely, "even taking into account that there are some differences between the proposals by Senators Hillary Rodham Clinton and Barack Obama, the impact of either on the deficit would be less than one-third that of the McCain plan." Let's do some math. McCain's plans will at "at least $5.7 trillion" whereas the Democratic plans will add "less than" $1.9 trillion to the deficit. The difference between them, in short, is at least $3.8 trillion.

That, obviously, is a huge difference -- larger than the net worth of Bill Gates or the GDP of Italy. There's no grounds for saying that two plans' costs have something "in common" when they differ in cost by at least $3.8 trillion, but to understand this you need to understand what you're talking about. After all, if one candidate was offering budget-busting on the Democratic scale, and another candidate was offering $2 trillion in deficit reduction nobody would have trouble distinguishing between the budget hawk and the deficit spender. But the difference in magnitude is the same in either case.