between the beginning of 2005 and mid-2007, no senator missed more roll-call votes than McCain did, except Tim Johnson, who was recovering from a near-fatal brain aneurysm.

from a MarketWatch opinion piece, “Why McCain Would be a Mediocre President”,
arguing that McCain has none of the qualifications he claims, had a weak military record and a weak Senate career, and owes his acclaim to his remarkable gift for self-promotion:

Instead of working on legislation or boning up on the issues, he’s been on “The Daily Show with Jon Stewart” more than any other guest. He’s been on the Sunday talk shows more than any other guest in the past 10 years. He’s hosted “Saturday Night Live” and even announced his candidacy in 2007 on “The Late Show with David Letterman.”

[MarketWatch]