The final surge came after Alabama beat South Carolina 20-6 and Florida needed a field goal in the waning seconds to beat Arkansas 23-20 at home.
The Crimson Tide, which received 10 first-place votes last week, got 39 out of 59 from the media panel. Florida received the other 20 first-place votes.
Texas is No. 3, followed by Southern California, Cincinnati and Boise State at No. 6. The Broncos dropped a spot.
The first BCS standings also came out Sunday and Florida was in first place, followed by Alabama, Texas and Boise State.
Unbeaten Iowa moved up four places after beating Wisconsin 20-10 on the road. Miami, LSU and TCU round out the top 10.
Alabama started the season ranked fifth, then immediately moved up a spot to fourth after beating Virginia Tech to start the season. After two weeks at No. 4, the Crimson Tide moved up another spot to No. 3.
After three weeks behind Florida and Texas, Alabama jumped the Longhorns last week and finished the climb to No. 1 on Sunday.
Alabama was No. 1 for five weeks in the second half of last season, including two weeks when SEC rival Florida was No. 2.
The Gators, the defending national champions, came into the season as an overwhelming No. 1, receiving the highest of percentage of first-place votes ever in the preseason poll.
But Tim Tebow and the Gators have sputtered offensively and had trouble putting away the better teams on their schedule. They had 10-point victories against Tennessee and LSU before beating Arkansas on a field goal with 9 seconds left.
Alabama's four SEC victories have been by an average of 19 points, with the closest margin being 14 against South Carolina.
Florida's four SEC wins have been by an average of 14 points, but that was padded by a 34-point victory against Kentucky.
"Saturday, after watching Florida give up big plays to an offense Alabama completely shut down, I decided to make the switch," said Andy Staples of SI.com. "Alabama, at the moment, seems to have fewer weaknesses than anyone else."
Alabama also has a nonconference victory against No. 15 Virginia Tech. Florida has played only one ranked team, LSU.
"I had been reluctant to make a switch at No. 1, even though Alabama has looked good all year," wrote Mike Strain, of the Tulsa World, in an e-mail. "But after Saturday, I voted Alabama No. 1, because I think the Crimson Tide has produced more impressive performances than Florida so far."