Obama, who has been criticized by the McCain campaign for being inexperienced, said it is a McCain administration that would be a leap for Americans, The Hill reported.

"At a moment like this, with so much at stake, we can't afford four more years of the tired, old, trickle-down, on-your-own philosophy that got us into this mess," he said in the Democratic radio address. "In this election, the biggest gamble we can take is embracing the same old Bush-McCain policies that have failed us for the last eight years."

Obama also said the change he promises to bring Americans will "not be easy," but can be accomplished.

McCain, in his radio address, said Saturday he plans to cut taxes and hammered Obama for wanting to "spread the wealth."

The Arizona senator also questioned his judgment and experience.

"In his four years in the Senate, two of them spent running for president, Barack Obama has displayed some impressive qualities. But the question is whether this is a man who has what it takes to protect America from Osama bin Laden, al-Qaida, the prospect of a nuclear-armed Iran and other grave threats in the world," McCain stated. "And he has given you no reason to answer in the affirmative."