I wanted to double check to be sure. But yes, the Communist Party did in fact support Roosevelt. Here’s an excerpt from a Jacobin article about the history of the party.

“The CP’s attitude toward President Roosevelt also evolved substantially. During the Third Period, he had been criticized on virtually every policy, even being called a “fascist.” During 1936, the party uneasily moved from advocating a Farmer–Labor party to tacit support for FDR’s reelection. The so-called People’s Front or antifascist coalition was eventually extended to include the Democratic Party.

In 1936, the party had criticized FDR for failing to lend aid to the embattled Loyalists in Spain. By 1937, it republished and lauded his speeches in the Daily Worker. In late 1937, it described him as “the most outstanding antifascist spokesman within the capitalist democracies.” At the May 1938, Tenth National Convention, the hall was decorated with American flags, and delegates sang the “Star-Spangled Banner” and a sanitized version of “The Internationale.” The party became Roosevelt’s abject apologists. When the president refused to support anti-lynching legislation, it blamed reactionaries in Congress and refused to criticize him directly. The CP blamed his policy on Spain on members of his cabinet. It even claimed at times to be the most consistent of New Dealers.” https://jacobin.com/2019/12/communist-party-usa-history