Mark Humphrey/AP

CNN poll: No clear vice presidential debate winner

Biden and Ryan were essentially evenly matched, voters say.

Instant polls conducted just after the debate between Vice President Joe Biden and Republican Rep. Paul Ryan were a mixed bag: A survey of registered voters who watched the debate by CNN/ORC found that 48 percent said Ryan won and 44 percent said Biden won.

The difference was within the poll’s margin of error of plus-or-minus 5 percentage points, prompting the network’s political analyst John King to say, “This was essentially a draw tonight. … What you have right here is a polarized America. I don’t think (the candidates) changed a lot of minds.”

A CBS News/GFK poll of uncommitted voters gave Biden the edge, with 50 percent saying they thought he won the debate, compared to 31 percent who said Ryan was the winner. Nineteen percent said it was a tie.

King noted that such polls have a very short shelf life, and anything they reflect about public sentiment will quickly be overtaken by next week’s debate between the main actors, President Obama and Republican nominee Mitt Romney, who will spar for a second time on Tuesday.

A focus group conducted by CNN during the debate produced similar results to the news network’s instant poll. A third of the 31 undecided voters participating said they thought Ryan won, a third said Biden won, and a third were undecided.  One pro-Biden participant said, “Compared with Obama’s performance (last week), he just didn’t allow the facts to be blown out of proportion without coming back at Paul Ryan. I thought he did a much better job than Obama did.”

A pro-Ryan participant said, “Ryan had a better command of the tax figures. And when he used figures to try to educate us, Biden would override him.” She said she thought Biden was “being a buffoon in general.”

CNN/ORC conducted interviews with 381 registered voters who watched the debates. CBS News/GFK polled 500 uncommitted voters.