Carvin made the announcement Friday morning as Republicans gathered in Rochester to pick an officially designated Senate candidate.
That leaves Nassau County comptroller George Maragos, New York City attorney Wendy Long and U.S. Rep. Bob Turner still in the field.
Carvin had been lagging behind in party support.
He says he initially got into the race when only Maragos had announced and he wanted to give GOP voters in the state a choice of candidates.
Copyright 2012 The Associated Press.