The Obama campaign released a new, national cable ad on Saturday responding to John McCain’s decision to tap Sarah Palin as his running mate. The message could not be clearer: Forget McCain/Palin, this ticket is all about McCain/Bush.

The negative ad comes just after Obama and Biden congratulated Palin’s progress, though not her positions, touting her on Friday as a "compelling new voice" whose assent marked an "encouraging sign that old barriers are falling in our politics." Picking up where that praise left off, the ad says McCain offers no change, given his economic policies and support for Bush. "He’s made his choice," the narrator sighs, "but for the rest of us, there’s still no change." The Obama camp is right to commend the Palin pick for breaking barriers — I had a similar reaction on Friday — and immediately return to savaging McCain for his elitist economic agenda and stubborn support for the failed Bush policies of the past.

The ad is below, followed by video of Obama speaking about Palin, and then a clip of an MSNBC debate I did from the Democratic convention. The debate focsed on McCain’s outreach to Clinton supporters and the prospect of putting a women on his ticket.

Update 2: Obama, flanked by Biden, speaks out on the Palin Pick:

Update 1: Politico’s Mike Allen says the "biggest risk" in Palin is that voters must embrace McCain’s humorous side:

Democrats are now the ticket of experience – 40 years in Washington vs. 36 years for the Republicans. Senator McCain is asking voters to assume he was just kidding about a basic premise of his campaign, both in the primaries and the general — that national-security experience matters when the country is at war.