Updated: 10:09 p.m.Rep. Ed Markey (D-Mass.) has opted not to run in the special election to succeed the late Sen. Edward Kennedy (D), leaving the field wide open for several Democrats — including at least two House Members — to run in the Dec. 8 Democratic primary. The dean of the Massachusetts delegation cited his seniority in the House and work as chairman of the Energy Independence and Global Warming Committee as his reasons for not running. “I believe that my leadership positions and seniority in the House allow me to accomplish more for my Congressional District and for Massachusetts,— Markey said in a statement. “I have therefore decided not to become a candidate for the Senate.—Markey is not the first big name in Massachusetts to opt out of running to succeed Kennedy. Former Reps. Joe Kennedy (D) and Marty Meehan (D), both of whom had amassed large campaign war chests, also announced this week that they are not interested in running. Former White House Chief of Staff Andy Card (R) announced Friday night that he would not run. “Now is not the right time for me to enter a political race,— he said in a statement.State Attorney General Martha Coakley (D) has already announced her campaign, while Reps. Stephen Lynch (D) and Mike Capuano (D) have retrieved the appropriate paperwork needed to run but have yet to formally launch a campaign.