A politically vulnerable House Democrat is speaking out against a popular bill that would rename the Department of the Navy.

Rep. Christopher Carney (D-Pa.) delivered a floor speech this week expressing his opposition to the bill, which would redesignate the Department of the Navy to the Department of the Navy and Marine Corps.

The bill, sponsored by Rep. Walter Jones (R-N.C.), passed the House by voice vote this week. It has broad bipartisan support, attracting a record 425 co-sponsors. The Senate companion, authored by Sen. Pat Roberts (R-Kan.) has 47 co-sponsors. Sens. John McCain (R-Ariz.) and Jim Webb (D-Va.) oppose the measure. And so does Carney.

In his speech, Carney said, "I have been a member of the United States Navy for more than 15 years and I am proud to be one of three members of Congress still serving in the Navy Reserve.

He added, "Past, present and future Marines should certainly be proud of the Corps, but also of the Department of the Navy. The Marine Corps was, is, and should remain, part of the Navy, both in name and in mission. A name change at the Department level will do nothing but foster animosity in the ranks of the Navy and Marine Corps. We should focus instead on the fight at hand and not worry about a change in nomenclature. Unfortunately, the spirit of H.R. 24 is counter to that notion."

Carney will face former U.S. attorney Tom Marino (R) in November. Sen. John McCain (R-Ariz.) won Carney's district by nine points over then-Sen. Barack Obama (D-Ill.) in 2008.