Analysis: And The Winner Is...

Oct.12. 2012 -- Partisan Democrats had a lot to be happy about last night's vice presidential debate, ABC News Political Director Amy Walter notes.

Vice President Joe Biden turned in an aggressive and energetic performance that they wished they'd seen from President Obama at his first of three outings against Republican presidential candidate Mitt Romney in Colorado.

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Republicans cried foul on Biden's behavior (GOP surrogates called him "rude," among other things.)In the spin room after the debate Sen. Rand Paul, referred to the vice president as "an arrogant Cheshire Cat."

"That sort of big grin," Paul said, "that he thought he knew more than anybody else."

GOP New Hampshire Sen. Kelly Ayotte called Biden out for "the smirking and the smiling." By contrast, Ayotte said, "Congressman Ryan looked vice presidential."

Meanwhile, Republicans argue that Rep. Paul Ryan's calm, unflustered demeanor and his solid performance on foreign affairs was appealing to swing voters, especially women.

Could they both be right? Sure. Democrats could get a spring back in their step, while swing voters also remain interested in hearing more from Romney-Ryan ticket.

Which, of course, makes the presidential debate next Tuesday all that more important.