Sen. Charles Schumer (N.Y.), head of the Democrats' policy and communications shop, said in a statement from his office that "on fundamental Democratic issues, Bob Menendez is one of the stalwarts in the Senate and is regarded as a invaluable leader in our party that helps keep us unified."
Ben Dworkin, director of the Rebovich Institute for New Jersey Politics at Rider University, said Menendez remains a solid progressive vote in the Senate despite a few disagreements with Democratic leadership and the White House.
"Most legislators, Senators certainly, would want to be able to say, 'I haven't been in lock step every time, and here is when I haven't been because I believe in the issue,'" Dworkin said.
Vice President Joe Biden waits to conduct a mock swearing-in ceremony with Sen. Brian Schatz, D-Hawaii, in the Capitol's Old Senate Chamber, December 2, 2014. Schatz was sworn in to serve the remainder of his term since he was appointed to the seat after Sen. Daniel Inouye, D-Hawaii, passed away.