No surprise, but the campaign is confirming it. Looks like Tom Crawford broke the news (subscription required) but I saw Tom linked off Blog for Democracy.
Michelle Grasso with Sen. Chambliss' campaign says they don't have a date or location yet, but Sen. McCain will be here.
"I just don't have a date yet," she said. "I've got a scheduling meeting at 2 o'clock."
Michelle said they've asked Gov. Sarah Palin to come, too, but no word on that.
No word yet on an Obama visit for Jim Martin yet, either, but you gotta think that's coming.
UPDATE: Coverage of Sen. Chambliss' initial announcement from Brunswick.