Can the officer smell alcohol and arrest me on that alone?

This distinction carries a great many of these cases, and it gets blurred constantly.

Florida law doesn't prohibit drinking and driving. It prohibits driving while your normal faculties are impaired, or with a breath or blood alcohol level at or above the limit. A person can have two beers with dinner, smell like it, and be entirely legal.

Odor establishes that alcohol was consumed. It says nothing about how much, when, or what effect it had. There's no basis for estimating impairment from smell, and officers generally concede on cross-examination that they can't quantify anything from odor.

Odor combined with other indicators builds toward probable cause. Odor by itself does not. And several of those other indicators have ordinary explanations — allergies, contact lenses, fatigue, and a natural speech pattern among them.

Worth knowing that Florida defines "normal faculties" specifically, including the ability to see, hear, walk, talk, judge distances, drive, make judgments, and act in emergencies. That's a more concrete standard than most people expect.