Obama’s opening statement talks about the “frustration” he’s seen in Pennsylvanians as he travels the state. Hillary’s notes that neither she nor Obama was represented when the Constitution was written in Philadelphia.

ABC’s odd two-hour format makes this debate a real marathon; neither one can go to the jugular too quickly. Perhaps ABC hopes for a gaffe as the night wears on, showing some exhaustion, but we should be set for fireworks as is after the increasingly feisty back-and-forth of recent days.

Gibson’s first question is about Mario Cuomo’s plan to make each one promise to select the other as running mate. An awkward silence follows, followed by laughter. Obama said talk of a veep now would not be prudent.

Hillary says she’ll do “whatever is necessary” to ensure a Democrat wins the election this year.