MONACA, Pa. – Barack Obama’s spokesman fired off a fast criticism of Republican John McCain’s new running mate Friday, but the Democratic candidate himself quickly stepped in to offer her congratulations and praise.

Obama, who is eager to win over female voters who backed his rival Hillary Rodham Clinton in the primaries, blamed the mixed messages about McCain’s choice, Alaska Gov. Sarah Palin, on campaign aides with a “hair trigger.”

He and his running mate, Sen. Joe Biden of Delaware, followed up with congratulatory phone calls to Palin.

McCain made his surprise announcement moments before Obama flew from Denver with Biden and their wives. Fresh off Obama’s nomination acceptance speech before 84,000 people Thursday night, the foursome launched a three-day bus tour of crucial industrial states, which began with a visit to a biodiesel fuel plant near Pittsburgh.

As the plane was lifting off from Denver, Obama campaign spokesman Bill Burton issued a statement calling Palin an abortion-rights opponent and “the former mayor of a town of 9,000 with zero foreign policy experience.”