Fellow republicans personally familiar with U.S. candidate believe the latter.
People who've worked with Republican Connie Mack IV say he's not the party boy that's depicted in Senate campaign ads, but rather a serious, hard-working politician who wants to carry on his father's tradition of promoting lower taxes and less government spending.
Mack's opponent, Democratic Sen. Nelson, has tried to smear Mack's character in ads that recall decades-old incidents involving bar altercations and road rage.
But Senate President Mike Haridopolos said when they were in the state House together Mack would rather go home and read bills looking for hidden tax hikes instead of hanging out at a bar popular with politicians.
Former Lt. Gov. Jeff Kottkamp said Mack was focused and learned a lot from his father, former Sen. Connie Mack III.