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My cousin is going to serve as a poll watcher.

In Official Documents:

Poll Watchers:

Political parties, candidates and some political committees are allowed to have

poll watchers in each polling room during the early voting period and on Election Day. Poll watchers must be approved by the supervisor of elections prior to the election. The supervisor of elections will provide each polling place a list of the names of approved poll watchers.

Florida Department of State
Division of Elections