John McCain's message machine shifted gears today -- after a week or so of offbeat efforts to annoy and exasperate Barack Obama, the Republican's campaign launched a new bid to distance him from the titular head of his own party.

A 60-second McCain television ad (see below) airing in several of this year's key battleground states seeks to both remind voters of the "maverick" image that gained him national prominence and undercut arguments that he's a President Bush clone.

Indeed, the spot's third sentence offers this starkly negative assessment of the incumbent's second term: "We’re worse off than we were four years ago."

We doubt Bush will embrace that talking point when he gets his moment at the podium on the opening night of the Republican National Convention in St. Paul, Minn.

And Obama's campaign certainly isn't buying it. As The Times' James Gerstenzang details on our Countdown to Crawford blog, the Democrat today sought to draw a straight line between the administration's energy policies and McCain.

[UPDATE: The Democratic National Committee also joined the fray, producing a video depicting McCain as the puppet of oil industry lobbyists.]

The McCain ad focuses on touting his credentials as one who can fix a "broken" Washington and does not directly mention Obama. But questions his campaign has raised about Obama's readiness for the White House are referenced in the ad's last line: "One is ready to lead: McCain."

Mark Silva notes in his posting on the Swamp that actor James Garner may have reason to take umbrage over the spot.

-- Don Frederick