Congressman Ed Markey won the Fifth Congressional seat once again on Tuesday night, beating Republican challenger Tom Tierney by a margin of about 3:1.

Thirty-six-year Congressional veteran Ed Markey secured the Fifth Congressional seat once again Tuesday night, winning out over Republican challenger Tom Tierney by a margin of about 3:1.

The Fifth Congressional District, newly reshaped during Massachusetts’ redistricting earlier in the year, encompasses parts of central Cambridge including Harvard’s campus. Previously, this area was represented by Congressman Michael E. Capuano, who was elected Tuesday to the new Seventh District.

Markey’s longtime incumbency and the left-leaning slant of the district prompted political experts and community members to anticipate his victory prior to the election.

“Honestly, this is Massachusetts,” said local politics pundit Robert Winters. “The Democrats just win the races and there’s not really a contest.”

After he voted in Cambridge on Tuesday, Cantabrigian Nunzi M. Sapuppo ’77 said, “Ed Markey’s done a great job.”

Democratic political strategist Mary Anne Marsh added that because of Markey’s strong efforts on the campaign trail, “what could have been a race and could have been a challenge doesn’t turn out to be.”

Markey, a ranking member of the House Natural Resources Committee, has championed legislation to promote the use of alternative energy.

The Massachusetts native is also the Dean of the Massachusetts Congressional delegation and spoke at the victory rally of U.S. Senator-elect Elizabeth Warren in Boston on Tuesday evening.

As Markey captured a seat in Washington, Democrats Marjorie C. Decker and Sal N. DiDomenico both won uncontested elections to represent districts that include most of Harvard’s campus on Beacon Hill.

DiDomenico, a state senator since 2010, currently chairs the Joint Committee on Community Development and Small Businesses. The Everett resident emphasized jobs as “always our number one priority in the state.”

Decker, who has garnered a reputation as a strong supporter of unions and veterans during more than a decade on the Cambridge City Council, said that in the State House, she would continue to fight for the issues she has championed.

Cambridge resident Tom O’Leary said of Decker, “She’s very pushy, but she endeared herself to us in numerous ways.”

—Staff writer Maya S. Jonas-Silver can be reached at mayajonas-silver@college.harvard.edu.

—Staff writer Nikita Kansra can be reached at nkansra01@college.harvard.edu.