Add Rep. Edward J. Markey to the list of politicians skipping a run for the late Edward M. Kennedy’s Senate seat.

Markey, a 17-term veteran of the House and the dean of Massachusetts’ congressional delegation, cited his seniority as a the reason he chose to forego the race.

He heads the Select Committee on Energy Independence and Global Warming; the Energy and Commerce Committee’s Subcommittee on Energy and the Environment; and serves on the Natural Resources Committee. “I can have the greatest impact on the issues facing the people of our state through my leadership positions in the House,” Markey said in a Friday afternoon statement.

He joins former Rep. Martin T. Meehan, Kennedy nephew Joseph P. Kennedy II and former Republican Lt. Gov. Kerry Healey on the sidelines.