State Sen. Bruce Tarr announced Thursday that he will not run for the open U.S. Senate seat.

Tarr, a Republican from Gloucester, represents Hamilton and Wenham in the state Senate.

Previously, Tarr said he was weighing a run and said he would make a decision by last Monday. The snowstorm delayed his decision, he said, and it was announced on Thursday night that he would not enter the race.

Democrats Ed Markey and Stephen Lynch are in the race, as are Republicans Dan Winslow and Gabriel Gomez. Former U.S. Attorney Muchel Sullican and former Congressional candidate Sean Bielat have both said in recent days that are considering a run.

The primary election is in April and the general election in June.