A spokeswoman for the Democrat confirmed his death on Monday.
He had been at the University of Pennsylvania Hospital in Philadelphia since last month, when he underwent emergency surgery for an infection in the tissue around his heart.
Adler was among the Democratic members of Congress who lost his job in last November’s election.
Adler grew up in the Philadelphia bedroom community of Haddonfield, where his father ran a dry cleaning business. When Adler was in junior high school, his father began having heart attacks that left him unable to work. He died before Adler was had graduated high school.
Adler went to Harvard College, then Harvard Law School. He was just 28 and back in New Jersey as a young lawyer when he won a seat on the township council in Cherry Hill.
In 1991, he was elected to the state Senate – the only Democrat that year to unseat a Republican incumbent in New Jersey’s legislative races. He was re-elected five terms and continued working as a lawyer.
He moved to Congress in 2008 by winning in a traditionally Republican district after longtime Rep. Jim Saxton retired. The open seat, coupled with a popular presidential candidate in Barack Obama, made a Democratic victory possible that year.
Circumstances shifted over the next two years, making his seat difficult to retain. Obama’s popularity had waned, and Adler was facing a well-known and well-liked Republican opponent in former Philadelphia Eagles lineman Jon Runyan.
The campaign brought to light a rare scuff on Adler’s reputation when a newspaper linked a third-party candidate’s campaign to area Democratic Party officials. The third-party candidate, Peter DeStefano, denied he was put up by Adler or Democrats, and Adler denied any involvement.
He was feisty and typically quick-tongued in what would be his last campaign. When Runyan said during a debate that the nation’s founders expected people to serve in government then return to civilian life, Adler retorted: “Most of our founding fathers, were, in fact, career politicians.”
But he ultimately lost the election.
According to JTA, Adler was among the first candidates in 2008 to endorse Barack Obama, later got flak from Orthodox Jews in the affluent town of Cherry Hill who believed that Obama had turned on Israel.