WASHINGTON — Republican Rep. Allen West said he believes 75-plus House Democrats are members of the Communist Party, a claim that echoed Joe McCarthy’s unsubstantiated 1950s charges that communists had infiltrated the top ranks of the U.S. government.

Addressing a town-hall meeting Tuesday in Florida, the freshman lawmaker was asked how many members of the American legislature are “card-carrying Marxists.” West said “there’s about 78 to 81 members of the Democratic Party that are members of the Communist Party.” He did not provide names.

West’s office said Wednesday that the congressman stood by the comments and was referring to the 76 members of the Congressional Progressive Caucus, the largest group within the House Democratic caucus.

“The Communist Party has publicly referred to the Progressive Caucus as its allies,” said Angela Melvin, a spokeswoman for West. “The Progressive Caucus speaks for itself. These individuals certainly aren’t proponents of free markets or individual economic freedom.”

West’s office cited a May 2010 article on health care that appeared in the Communist Party USA pre-convention publication that described the Progressive Caucus and Rep. John Conyers, D-Mich., as allies of the party but not members. The article, however, carried the disclaimer that Communist Party USA “takes no responsibility for the opinions expressed in this article or other articles in the pre-convention discussion.”

The caucus, founded in 1991, includes 75 House members and one senator and describes its goals as economic fairness, civil rights, environmental protection, energy independence and global security. A congressional aide said the caucus was preparing a response to West.

The Palm Beach Post first reported the congressman’s comments.

During the Cold War, McCarthy, a Republican senator from Wisconsin, claimed that communists and Soviet spies had burrowed their way into the federal government. He never produced the names or documentation to back up his claims.