With the ink barely dried on the news Saturday morning that Barack Obama had chosen Joe Biden as his running mate, John McCain's campaign released a TV ad using Biden's own words against Obama.

In particular, the ad shows 2007 footage of an ABC debate with the Democratic presidential candidates in which Biden affirmed his belief that Obama is not ready to be president.

"You were asked, 'Is he ready?'" the moderator, ABC'sGeorge Stephanopoulous, says to Biden. "You said, 'I think he can be ready but right now, I don't believe he is. The presidency is not something that lends itself to on-the-job training,'"

"I think that I stand by the statement," Biden responds, with Obama standing to his right on the stage.

The ad also shows Biden on a 2005 segment on "The Daily Show" saying, "I would be honored to run with or against John McCain, because I think the country would be better off."

Click here to view the video.

The ad was the McCain campaign's opening shot against the newly completed Democratic ticket, which was announced by the Obama campaign Saturday morning after the news was leaked to reporters. Biden and Obama -- both senators, as is McCain -- are scheduled to appear together at 2 p.m. CDT in Springfield, Ill., before heading to Denver for next week's Democratic convention.

Biden is one of the most influential foreign policy voices in Congress, which could shore up Obama's foreign policy credentials, Biden also is known for speaking his mind, something the McCain campaign is sure to capitalize on.

But McCain's vice presidential pick could face similar scrutiny once the name is announced -- likely on Friday, after the Democratic convention and before the Republican convention, which starts Sept. 1.

Former Massachusetts Gov. Mitt Romney is one of the leading contenders for the spot on McCain's ticket, and while he was still in the running for the Republican presidential nomination Romney got in his share of jabs at McCain, during debates and on the campaign trail.