the problem for any candidate is, that the country is divided among so many lines, that no matter which political spectrum you belong to, you have to win over the center to win the election. That's why Obama is talking religion now, that's why he's talking guns and national security, that's why he talks tough on Iran.
Same with McCain, if it wasn't for the moderate center, he would sound a lot more like Karl Rove, although he's one of the most moderate Repulicans and a man of character.
the two candidates are very different, and both are a quality choice for America, if you compare some of the previous races. to us Europeans, the whole process might look really screwed-up at times, but a country that size, with that sort of diversity and political divide, it's gotta be messy and as a president you won't be able to cater to everyone. whoever wins, will be a compromise president. tough on national security, yet green on climate issues, more protectionist than previous administrations, etc...
on a sidenote, if you want to blame anyone for the mess that is American politics, blame cable news. that's the most shameful part of american political culture these days (and it has been for years). i applaud the wide spectrum of free speech late night talkers and commentators, but if you look at what the majority of people are actually watching at the center, those aren't news, that's preaching to the converted. to all the non-americans in here; have you ever watched Fox News? scary horrible ... shudder