Many clients have condos in Florida, but their primary residence is here in the northwest suburbs of Chicago. Of that group, some choose to become Florida residents and change their "domicile" to Florida.
New York attorney Allan Lipman has put together a nice on-line audio seminar that explains many of the issues that surround making Florida your residence. While he mainly covers New Yorkers with condos in Florida, the concept is the same for Illinois residents. Give it a listen if you are considering making Florida your tax and voting "home."