According to the widely respected Tax Policy Center, analyzing the candidates' campaign platforms:
"The simple bottom line: under Senator Obama’s tax plan as described by his campaign advisors, the ten-year federal deficit (before spending cuts) would total nearly $5.9 trillion; a comparable total for Senator McCain’s tax plan is almost $7.4 trillion. Expanding each candidate’s plan to include proposals made in stump speeches yields ten-year deficit totals (again before spending cuts) of $5.4 trillion for Obama and almost $11 trillion for McCain."
Neither candidate's spending cuts are included due to a lack of specificity from both in saying what these would be.
On the spending side, I'd say the ten-year McCain total is several trillion dollars too low given the foreign military adventures he would engage in.