So what happens in Foley's district?

From Florida Code, Chapter 100.111, 4(a):

"(4)(a) In the event that death, resignation, withdrawal, removal, or any other cause or event should cause a party to have a vacancy in nomination which leaves no candidate for an office from such party, the Department of State shall notify the chair of the appropriate state, district, or county political party executive committee of such party; and, within 5 days, the chair shall call a meeting of his or her executive committee to consider designation of a nominee to fill the vacancy. The name of any person so designated shall be submitted to the Department of State within 7 days after notice to the chair in order that the person designated may have his or her name on the ballot of the ensuing general election. If the name of the new nominee is submitted after the certification of results of the preceding primary election, however, the ballots shall not be changed and the former party nominee's name will appear on the ballot. Any ballots cast for the former party nominee w ill be counted for the person designated by the political party to replace the former party nominee. If there is no opposition to the party nominee, the person designated by the political party to replace the former party nominee will be elected to office at the general election."

How about George P. Bush? Dan Marino?  Shaq?