From CBS News' Dante Higgins:
APPLETON, WIS. -- In the skies between Texas and Wisconsin today, John McCain spoke with reporters following his endorsement by former President George H.W. Bush.
He admitted former President Bush didn't offer him any special advice today other than to "keep going."
"He's such a gentleman, such a good hearted guy. Couldn't have been nicer," McCain said. He added that the current President Bush is welcome to step into his campaign at anytime and anywhere he wants.
"We would sit down and talk about that at the right time but I'll be glad to have him with me under any circumstances," said McCain.
Meantime, McCain campaign adviser Mark McKinnon has made news recently by stating publicly that he will step down if McCain and Barack Obama are the presidential nominees of their parties. On National Public Radio last week, McKinnon said he would be uncomfortable in a campaign that would be attacking Obama.
"Could I just say no matter what happens, I love Mark McKinnon, I have the greatest respect and appreciation for him, because when we were really difficult times, McKinnon did those ads for free," McCain said about the campaign ads that were produced last year when he was having trouble raising money.
"He did those and he came up with them. I'm not sure we... would have in any way succeeded without Mark's incredible help, and I'll always be grateful," he said.
Over the weekend, while not campaigning, McCain met with his advisors to discuss his strategy moving forward.
"We really just talked about overall strategy, campaign themes, what we expect - nothing earth-shaking that I know of. But it was important for us to sit down look at where we are, where we have been."
He says we can expect the themes of his campaign to remain the same as he shifts into general election mode. "Fix the economy, healthcare, national security, take care of the veterans. All of the things we talk about on the campaign," he said.
"The economy has kind of overshadowed health care a little bit. Health care is still out there but it's not the first question, the first question is now the economy overall... So, we're going to talk a lot about the economy obviously."