Here is your answer. Although the column varied in the number of newspapers, at its height it was in 90 papers,up from 62 in 1938. Some of the major city newspapers are mentioned below.
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My Day" was the six-day-a-week newspaper column Eleanor Roosevelt wrote from December 30, 1935, until September 27, 1962. In 1961, at Eleanor Roosevelt's request, the column appeared every other day until September 26, 1962 when she grew too ill to work. Nationally syndicated, at its height the column appeared in ninety papers in all parts of the nation, providing ER with a reading audience of 4,034,552, ranking her immediately below Dorothy Thompson, the leading female columnist of the era.
The newspaper column began and originally was syndicated by the United Features Syndicate By 1938, her United Features Syndicate column appeared in 62 newspapers,
My Day." United Features Syndicate (January 1936-October 1962). Major clients include: Birmingham Post, Los Angeles Daily News, Washington Daily News, Chicago Sun-Times, Boston Globe, New York World -Telegram, Memphis Press-Scimitar, Dallas Times Herald, Seattle Post-Intelligencer, and Madison Capital-Times.
By 1940, interest in "My Day" was so strong that United Features Syndicate offered her a five-year contract even though it had no expectation that the Roosevelts would remain in Washington for another term.
While a member of the American delegation to the United Nations, ER tried to temper her partisanship and used the column to introduce Americans to the complexities of the UN and the Universal Declaration of Human Rights drafting process; however, when President-elect Dwight Eisenhower refused to reappoint her to the delegation in 1953, she no longer had any reason to moderate her language. By 1954, "My Day" had become her political platform, as well as her diary of her political activities. It was the major venue in which she challenged complacent Democrats, timid liberals, and apathetic Americans to accept the responsibilities of living in a democracy. By 1957, political commentary so dominated the column that the Scripps Howard syndicate dropped "My Day" for being "too political." By 1960, she waged a consistent battle with those political leaders who were more concerned with "profile than courage" and urged her readers to follow their consciences rather than their fears.