Barack Obama’s latest campaign ad questions the selection of Alaska Gov. Sarah Palin as John McCain’s running mate.

The ad, “His Choice,” features soft music playing with an image of McCain on the screen that highlights past comments McCain has made about his own understanding of the U.S. economy.

“The issue of economics is not something I’ve understood as well as I should,” reads one quote, cited from a Dec. 2007 Boston Globe story. The ad then notes McCain’s comment from a Republican primary debate last November that he “might have to rely on a vice president I select” as a backstop on economic policy.

The screen then flashes to the words “His Choice?” and then cuts to a slow motion image of Palin giving her signature wink to the camera during the vice presidential debate earlier this month.

The 30-second ad will air in battleground states. It is the first time Obama’s campaign has called into question McCain’s judgment selecting Palin as his vice president in a television ad.

As The Wall Street Journal reports today, Palin will be campaigning in Toledo, Ohio, to give a speech on energy policy.

The McCain-Palin campaign has been dogged in recent days by multiple reports of a growing rift between the staff and the running mates over the campaign’s direction, as well as pointing fingers over who is to blame for recent gaffes including Palin’s $150,000 wardrobe expenses. Unnamed McCain advisers have referred to Palin as a “diva” to CNN and a “whack job” to Politico.