- The maverick thing - yes it's overplayed and McCain's flipped on a lot of things to get the nomination, but it's also partly real. Where has Obama bucked Democratic Party orthodoxy?
- Ethanol - McCain opposes domestic ethanol subsidies and the 54-cents per gallon tariff on Brazilian cane ethanol. The domestic ethanol is bad while the Brazilian ethanol might be environmentally okay. Obama takes the opposite position on both, and is tied intimately to Big Corn.
- Fighting wasteful military spending - McCain has done this, while I'm not aware of Obama taking on anything yet.
Other suggestions are welcome, especially ones that aren't along the lines of "McCain is more conservative than Obama on issue X, and I believe the conservative position is better, so McCain's better."