Sen. Hillary Clinton will not attend the event but recently campaigned with Obama in Florida, a battleground state that CNN considers a toss-up.
The Clintons also campaigned with Sen. Joe Biden and Biden's wife, Jill, in Scranton, Pennsylvania, where both Joe Biden and Hillary Clinton have roots.
Obama met with Bill Clinton in September at Clinton's Harlem, New York, offices. Then, Clinton predicted that Obama would win in November "pretty handily."
The Illinois senator levied more criticism at opponent Sen. John McCain on Saturday, mocking the Arizona Republican by saying McCain is just "trying to break with his president over the last 10 days after having supported him for the last eight years."
"He denounced the president for letting things get completely out of hand; that's what he said," Obama told a crowd in Reno, Nevada. "In fact, John McCain is so opposed to George Bush's policies that he voted with him 90 percent of the time for the first eight years. That's right, he decided to really stick it to George Bush -- 10 percent of the time.
"So, let's be clear. John McCain attacking George Bush for his out-of-hand economic policy is like Dick Cheney attacking George Bush for his go-it-alone foreign policy. What Joe Biden says: It's like Tonto getting mad at the Lone Ranger."
It's not clear Obama's running mate ever said that publicly. Biden has, however, made similar references using Butch Cassidy and the Sundance Kid.
Obama is spending the day in the west. In addition to Reno's event, he's holding a rally in Las Vegas and one in Albuquerque, New Mexico.
Meanwhile Saturday, GOP vice presidential candidate Gov. Sarah Palin said that electing Obama, combined with a Democratic majority in Congress, will lead to government helping to run families.
Palin told Iowans that under Obama's "big government agenda," their income, property and investments would be "shared with everybody else."
She labeled Obama's plan to provide tax credits to lower and middle-income wage-earners "the philosophy of government taking more, which is a misuse of the power to tax."
"It leads to government moving into the role of taking care of you, and government and politicians, and kind of moving in as the other half of your family to make decisions for you," she said in Sioux City. Fact Check: Obama's tax plan
With audience members shouting "socialist!" throughout her speech, the Alaska governor said that time is running out for Americans to realize the danger of a having a Democrat in the White House.
At the beginning of her remarks, Palin referred to her much-discussed wardrobe, which has the been the subject of scrutiny since Politico reported that the Republican National Committee spent $150,000 on clothes for Palin and her family before the convention.
"Your state is filled with good, hard-working people all loving the outdoors," she said, "and it was nice and crisp getting off the airplane and coming into the -- it reminded me a lot of Alaska, so I put my warm jacket on, and it is my own jacket. It doesn't belong to anybody else."
McCain spoke in Albuquerque, saying Obama doesn't understand issues of the American West.
"I know them,' he said. "I know what the Southwest is, I know strength and the culture and our Hispanic culture and the strength of our great states."
Meanwhile, Obama unveiled a TV ad Saturday that puts a new spin on the question, are you better off today than you were four years ago?
The two-minute ad, "Defining Moment," will begin airing in key states Sunday, according to the Obama campaign.
"At this defining moment in our history, the question is not, 'Are you better off than you were four years ago?' We all know the answer to that," Obama narrates.
"The real question is, 'Will our country be better off four years from now?' How will we lift our economy and restore America's place in the world?" Watch the full ad here
In order to "build the economy of the future," Obama says, the focus must be on "urgent national priorities: reducing the cost of health care ... breaking our dependence on foreign oil ... and making sure that every child gets the education they need to compete."
The ad comes just a day after McCain's campaign launched a TV ad attacking Obama's readiness to lead in an international crisis.
"Listen to Joe Biden," the ad's narrator states before playing a recording of Biden saying: "It will not be six months before the world tests Barack Obama. ... We're going to have an international crisis, to test the mettle of this guy."
"It doesn't have to happen; vote McCain," the narrator says.
Biden's comments have also become a fixture of both McCain and Palin's stump speeches as they look to stress what they call the Illinois senator's relative lack of foreign policy experience. The McCain campaign says the ad will run in key states.
At a rally in Norfolk, Virginia, on Saturday, Biden discussed Obama's new ad and blasted the McCain campaign's tactics.
"You know how we're finishing out the campaign? Barack is going up, instead of anything negative, we're going up and laying out our plan to fix the economy. That's what we're running on," Biden said. "What is the McCain campaign continuing to do? They want to do anything but talk about the economy."