(CNN) - Massachusetts Rep. Stephen Lynch announced Tuesday he will forgo a run for the Senate seat long held by the late Sen. Ted Kennedy.
In a statement, the four-term congressman said he is unable to build the necessary campaign infrastructure ahead of the December 8th Democratic primary.
"The challenge of putting together the resources and organization necessary to wage a competitive statewide campaign in less than 90 days is insurmountable," he said in the statement. "I have been given a huge honor and responsibility by the families of the 9th Congressional District of Massachusetts. I will continue to try to live up to their highest expectations.”
Lynch’s decision comes a week after he signaled that he would run for the seat - pulling the necessary paperwork to launch a campaign.
He is only the latest in a string of Massachusetts Democrats who have recently announced that they will not run for the seat held by Kennedy for more than four decades.
Reps. John Tierney and Edward Markey both said they would not run, as did former Reps. Marty Meehan and Joseph Kennedy, Jr., the late senator's nephew. Meanwhile, Rep. Mike Capuano has obtained the necessary paperwork, but has yet to say if he will run.
Only the state's attorney general, Martha Coakley, has formally launched a campaign for the seat.
On the Republican side, former Bush Chief of Staff Andrew Card briefly flirted with the possibility of launching a bid, but ultimately declined. State Sen. Scott Brown has officially jumped into the race and is considered the frontrunner for the party's nomination.
The general election will be held on January 19.