"He will have a role as one of my advisers,"said on NBC's "Today" in an interview aired Monday, a day after Powell, a four-star general and President Bush's former secretary of state, endorsed him.
"Whether he wants to take a formal role, whether that's a good fit for him, is something we'd have to discuss," Obama said.
Being a top presidential adviser, especially on foreign policy, would be familiar ground to Powell on a subject that's relatively new to the freshman Illinois senator. Obama has struggled to establish his foreign policy credentials against GOP candidate, a decorated military veteran, former prisoner of war and ranking Republican on the Senate Armed Services Committee.
In the NBC interview, Obama said Powell did not give him a heads-up before he crossed party lines and endorsed the Democratic presidential candidate on the network's "Meet the Press" a day earlier.
In that interview, Powell called Obama a "transformational figure" in the nation's history and expressed disappointment in some of McCain's campaign tactics. But, Powell said, he didn't plan to hit the campaign trail with Obama before the Nov. 4 election. ()
"I won't lie to you, I would love to have him at any stop," Obama said with a grin Monday. "Obviously, if he wants to show up he's got an open invitation."
On CBS' Face The Nation, supporters of both campaigns reacted to the endorsement.
Republicans Gov. Matt Blunt of Missouri and former Rep. Rob Portman of Ohio both said they don't think the endorsement would affect the race in their states, both battlegrounds.
"I don't know that it will make a difference in Missouri. You know, Missourians admire Colin Powell for his many years of service to our country, but in the end they're going to evaluate where the candidates on issues that are important to them," Blunt told host Bob Schieffer.
"I don't think it makes a big difference," added Portman. "Endorsements are typically overrated I think. But Colin Powell is well respected. I was interested to see that he said this morning that he thought either man would be a good president. It didn't surprise me a lot because I've heard General Powell talk about both candidates. He says he respects both men but he's always had a special admiration for Senator Obama."
But Democratic Gov. Tim Kaine of Virginia had a different view, saying he thought the endorsement would make a difference in favor of his candidate and calling it "very important" in his state.
"General Powell is not seen as a dividing figure but a uniting figure. And so him vouching for Senator Obama convinces those of us who want to see a greater unification of the nation that he's the right guy," he said. "Second, General Powell is not an ideological figure. He's a pragmatic person. And so those of us who are, you know, pragmatists first who worry about results and just trying to do the right thing and manage government well, I think they'll see the endorsement by General Powell very positively. Finally it vouches for the senator in terms of that critical issue. We know he has plans to make a change in direction of national security policy. To have the confidence of General Powell in this election is very important. Virginians care about this. We're a state that loves the military. A lot of installations, a lot of folks in service or veterans. So General Powell's endorsement will mean a lot to Virginians, especially the undecideds and Independents."
Democratic Rep. Debbie Wasserman Schultz of Florida said she also thought the endorsement would "resonate" there.
"We have thousands of military retirees in the state of Florida," she said. "And I think what Colin Powell's endorsement does say is it shows that Barack Obama can build bridges across party lines. He's going to be able to reach out and bring in and embrace different ideas and, you know, isn't necessarily, you know, cut from one particular cloth." ()
Powell's endorsement came just hours after Obama's campaign disclosed that it raised- obliterating the old record of $66 million it had set only one month earlier.
He expressed disappointment in the negative tone of McCain's campaign, his choice of Alaska Gov.as a running mate and their decision to focus in the closing weeks of the contest on Obama's ties to 1960s-era radical William Ayers, saying "it goes too far."
McCain, meanwhile, seemed dismissive of Powell's endorsement, saying it wasn't a surprise, that the two share mutual respect and are longtime friends.
The Republican from Arizona pointed out on Sunday that he had support from four other former secretaries of state, all veterans of Republican administrations: Henry Kissinger, James A. Baker III, Lawrence Eagleburger and Alexander Haig.
At a boisterous rally Sunday, Obama said McCain was "out of ideas and almost out of time."
He and his aides appear so confident of his prospects that apart from a brief stop in Madison, Wis., next Thursday, Obama currently has no plans during the next 10 days to return to Pennsylvania, Minnesota, New Hampshire or any other state that voted for John Kerry in 2004.
Instead, he intends to spend two days this week in Florida, where early voting begins on Monday, and travel to Virginia, Iowa, Ohio, Colorado, New Mexico and possibly Nevada and Indiana. Those states hold 97 electoral votes combined, and Bush won all in 2004.
Obama also may stop in West Virginia, where his campaign recently bought statewide television advertising in a late attempt to put the state's five electoral votes into serious contention.