Conn. Gen. Stat. § 9-35b

Except during the period between the last session for the admission of electors prior to an election and the day following that election, any elector of any municipality who desires to relinquish his rights as an elector and to have his name erased from the registry list shall make a signed written request to the registrars of voters of such municipality. Upon receipt of such application, the registrars shall remove the elector's name from the registry list and any enrollment list. Any person whose name has been removed from the registry list pursuant to this section may reapply for admission as an elector at any time, without prejudice on account of such removal. In the event such person is admitted as an elector, the registrar of the municipality shall notify the registrars of the municipality where such person resided at the time of his relinquishment that his electoral privileges have been restored.