I took a look at that Martinez/Castor race to see where she did better than Kerry, perhaps in indication of where "Old Florida" may have supported her, or at least some of it. Perhaps those of you more familiar with Florida can glean something from the results, where Harris might do better than Martinez. In the other counties, Bush and Martinez ran almost even or in similar proportions. This is what was significantly different for me to note.
Martinez dropped a few thousand votes in Citrus County, turning a nearly 10,000 vote lead for Bush into a near 3,000 vote lead for himself.
Dixie County: Again, dropoff for Martinez and bump for Castor, though he still won the county. Dropoff was about 1,000 votes.
Duval: Martinez still had a big win over Castor, but Bush's win was bigger by about 15,000.
Flagler: Martinez loses narrowly while Bush wins by about 1,000.
Franklin: Same as Flager
Hamilton: Martinez narrowly loses, Bush narrowly wins, with each under a margin of 1,000 votes.
Hillsborough: One of the biggest splits in the vote count. Bush wins by 31,444 votes, while Martinez loses by 22,967.
Lafayette: Tiny county here. Goes for Bush in a landslide, while breaking almost even for Martinez and Castor.
Liberty: Barely goes for Castor by 11 votes. Bush gets about a 900 vote margin here.
Madison: Another Bush/Castor county. Bush squeaked by, Martinez lost by about 1,000.
Manatee, Marion: Martinez drops about 1,000 from Bush's total in each of these counties, while Castor picks up from Kerry's total by about 4,000. (Martinez still wins these, though)
Martinez narrowly won Miami-Dade, doing much better than Bush (Not that he was expected to win it anyway).
Martinez narrowly carried Orange County by 572 votes, while Bush lost it by only 815 votes.
Pasco was not as kind to Martinez as to Bush, shaving off about 10,000 from Bush's total to Martinez. Castor gets a 6,000 vote boost here from Kerry.
Bush scraped out a narrow win in Pinellas County by 226 votes, while Martinez lost it by 36,811 votes. Perhaps the biggest split between the presidential and senatorial races.
Martinez drops about 20,000 in Polk County, and Castor picks up about 7,000 from Kerry's.
Sarasota delivers another hit to Martinez, giving him only a 4,000 margin over Castor, while Bush wins it handily.
Volusia: Bush didn't win this county, and neither did Martinez, though he loses by a bigger margin, dropping 7,000 from Bush's total.
Well, at least we know why the Florida senate race was such a nailbiter. Bush's high turnout is probably got Martinez over the finish line, or at least out of recount territory.
I think a lot of the difference between the Bush and Martinez totals was due to Castor's and Martinez's respective "home-field advantage." Castor is from the Tampa Bay area, which helped her run far stronger than Kerry in Hillsborough, Pinellas, Pasco, Polk, Sarasota and Manatee Counties; Martinez is Cuban and is from Orlando, which helped him run stronger than Bush in Miami-Dade and Orange Counties.
The other area where Castor outperformed Kerry was in conservative North Florida, which is the most "Southern" part of the state and which is historically Democrat but not anymore in presidential races. Martinez was unable to get as many conservative Democrats to vote for him as President Bush did---then again, Martinez was not the Commander-in-Chief leading the War on Terror.
As I wrote before, I don't think we can glean much information regarding how "Old Florida" voted based on county results, since "Old Florida" voters could be living next door to recent retirees from Pennsylvania and wealthy Cuban businessmen. But the "Old Florida" theory certainly helps to explain how Lawton Chiles and Bob Graham were able to win so many statewide elections in the face of very strong pro-GOP tides.