President Obama has struck a new ideological tone, albeit without a wholesale revision of his policies. Now he must find a new label, since a Rasmussen poll released last month showed the popularity of the tag "progressive" sinking like a stone.

His search will be complicated by the long, tortuous history of rebranding on the left. As the Cold War dawned, American Communists, who were still a formidable force, sought a rebirth by christening themselves "Progressives," a moniker usurped from the reform movement of the Teddy Roosevelt era. They created the Progressive Party, which ran former Vice President Henry Wallace for president on a platform blaming America for the Cold War.

During the years when Communists appropriated the "progressive" label, left-of-center anti-Communists called themselves "liberals." In New York, they formed the Liberal Party as an explicit alternative to the Communist-controlled American Labor Party, which was part of the Progressive Party. In labor unions and numerous cause groups advocating civil rights, civil liberties and social welfare measures, these "liberals" battled against the Communists and their fellow-travelers, the self-styled "progressives."

When the Communists precipitously lost popularity in the 1950s, the word "progressive" fell into desuetude. A New Left emerged in the 1960s that at first boasted of being "radical." But most of the movement's adherents learned that this term was self-defeating, so they took to calling themselves "liberals." This tactic paid off handsomely in 1972 when their hero, George McGovern, a delegate to the Progressive Party convention in 1948, won the Democratic presidential nomination.

By the late 1970s, these activists had seized control of the Democratic Party and most of its cause groups. Meanwhile, they branded the older-style liberals "neoconservatives" (a term seemingly coined by the socialist philosopher Michael Harrington in 1973), and they succeeded in capturing sole control of the "liberal" banner.

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