One Obama campaign e-mail, for example, cited an editorial in the Fairbanks Daily News-Miner, which said Palin "has never publicly demonstrated the kind of interest, much less expertise, in federal issues and foreign affairs that should mark a candidate for the second-highest office in the land."
Republican Lyda Green, president of the Alaska Senate and someone who has occasionally clashed with Palin, told the Anchorage Daily News, "She's not prepared to be governor. How can she be prepared to be vice president or president?"
McCain and his campaign have emphasized that Palin got involved in politics to fight corruption and wasteful spending, and that her challenge to the political status quo rocketed her to the governor's mansion in a short period. They also said her years as mayor compare favorably to the résumé of Obama, a first-term U.S. senator.
"By the way, Gov. Palin has more executive experience" than Obama, former Pennsylvania governor Tom Ridge said earlier at the ballpark rally.
Ridge added, "I smell victory, but we've got to win Pennsylvania.
"She's a tough politician," GOP strategist Rich Galen said Saturday. "She understands how the game is played."
In introducing his running mate, McCain cited Palin's middle-class roots and said she is someone who understands the problems of real people. He called her a "great governor" who has worked with both parties, showing "great tenacity and skill in tacking tough problems."
Pennsylvania, which has voted Democratic in four consecutive presidential elections, is a key to winning on Nov. 4. The rural, western areas around Pittsburgh are crucial to McCain's hopes of capturing the state's 21 electoral votes, Pennsylvania pollster Jim Lee said.
Lee said McCain and Palin need to offset what is expected to be a strong vote for Obama and Biden in Philadelphia and its increasingly Democratic suburbs. Philadelphia has the state's largest concentration of black voters, which tend to vote Democratic. The city's TV market also reaches Delaware, which Biden has represented in the U.S. Senate for more than 30 years.
Palin's opposition to abortion rights should help sway voters in central Pennsylvania, around the capital of Harrisburg, and in the western part of the state, according to Lee.
"Voters in these areas are much more conservative on social issues," he said.