McCain added that if elected president, he would appoint managers to work beneath him, rather than seek that role for himself -- a dig at Romney's repeated assertion that his experience as a manager in the business world should qualify him for the presidency.

"I can have lots of managers, but I believe I'm qualified to lead, and I have a record to prove it," McCain said. "I will lead, not manage. That's what the American people want."

McCain campaigned with Sen. Mel Martinez (R-Fla.), who endorsed his colleague on Friday. Martinez said he will work hard to drum up support for his colleague both among Cuban Americans in the Miami area and among voters in the Interstate 4 corridor between Tampa and Orlando, "where this election will be decided, as they often are."

Martinez told reporters that he thinks "overperforming in southeast Florida" among Latino voters could help McCain edge out Romney. "It made a huge difference in my race," he added.

While Martinez acknowledged the race is highly competitive, he said McCain enjoys the advantage of being known by many Florida voters, especially among Latinos and Jews because they are "communities that are impacted by what happens abroad."

While McCain and Romney clashed Friday and Saturday over their economic and foreign policy qualifications, Giuliani attempted to take advantage by proclaiming himself the best of both worlds.

"I've had experience in both areas and results in both areas," Giuliani told a crowd at the Columbia Restaurant in Sarasota.

But Giuliani's message was quickly overtaken by the angry back-and-forth about Iraq, leaving the former mayor once again on the sidelines as he seeks a victory in the one state where he has campaigned vigorously.