Time Magazine just put up an article that pretty neatly summarizes McCain's chances in November, and it's not very optimistic.
Foreign policy issues are looking to be less and less of an advantage for his campaign, and he's looking weaker and weaker on the economy. The past week or so has been particularly bad:
• The argument that talking to rogue states as 'appeasement' seems more baseless than ever since the Bush administration moved towards more normal relations with Iran
• Prime Minister Maliki more or less endorsing Obama's plan for withdrawal from Iraq, forcing McCain to make some pretty awkward decisions about where that leaves his 'time horizon' plan
• Obama's tour of Europe and the Middle East, a mix of high-level policy meetings with more rockstar-like events, will dwarf most news from the McCain campaign for a while and do a lot to erode perceptions of foreign-policy naivete.
I'm still keeping my fingers crossed, McCain came back from almost nothing in the primaries, but this election is definitely Obama's to lose.