Some GOP advertising experts and delegates to the convention believe so.
Within minutes of the speech's end Wednesday night, they predicted it could make Mr. Obama's and running mate Sen. Joe Biden's jobs far more difficult.
"For someone who has never set foot on the national stage, she seemed very comfortable. She was using all the tools: toughness, humor, sarcasm and using them all with confidence," said Vinny Minchillo, chief creative officer of Scott Howell & Co., Dallas, a GOP ad shop.
"Going forward, her performance [indicates] she's more than willing to wade into a fight. What's very scary, if you're on the other side, is that she can tear your head off and do it with a smile, something Joe Biden is unable to do. The Democrats will have to find a new way to do battle with Palin. This could get ugly."
Delegates and attendees at the convention had the same opinion.
"I'm a former speech teacher," said Jennette Gudgel, secretary of the St. Paul Republicans. "It was well done. She knows what she was talking about."
Cindy Coleman, an alternate delegate from Tucson, Ariz., said Ms. Palin "came in with the feistiest attitude. ... So positive and upbeat ... a breath of fresh air. I knew that she was a polished speaker, but it was really amazing that she really took on the other candidates."
Democrats were far less convinced.
Obama campaign spokesman Bill Burton issued a statement calling the speech "well delivered" but "divisive."
"The speech that Gov. Palin gave was well delivered, but it was written by George Bush's speechwriter and sounds exactly like the same divisive, partisan attacks we've heard from George Bush for the last eight years. If Gov. Palin and John McCain want to define 'change' as voting with George Bush 90% of the time, that's their choice, but we don't think the American people are ready to take a 10% chance on change," said Mr. Burton.
And Campaign Manager David Plouffe released a statement to Obama supporters defending "community organizing," which had been turned into a Republican punchline by the end of the evening. "Community organizing is how ordinary people respond to out-of-touch politicians and their failed policies," he said.
The speech's eventual impact could be determined by the number of people who saw it, which won't be known for a day or so. But in tone and message it seemed to spell out an approach to the campaign put forth by Mr. McCain's campaign manager.
He said in an interview that personalities and backgrounds rather than issues will be the major factor in voting this November. The Obama campaign has said it believes issue differences rather than personality will decide the results.