McCain's campaign was poorly run and much more negative than Obama's. Between his pick of Palin for VP, his suspended campaign stunt, and all of the negative campaigning (Ayers, ACORN, Socialist, etc.), I'm not surprised he got so much bad press.
And are you really surprised Obama got such good press? He's charismatic with many, many loyal followers who got out the vote for him. Simply covering that story would get him more good press than McCain.