 The large, mostly spontaneous gatherings at Truman's whistle-stop events were an important sign of a change in momentum in the campaign, but this shift went virtually unnoticed by the national press corps. It continued reporting Republican Thomas Dewey's apparent impending victory as a certainty. One reason for the press'inaccurate projection was that polls were conducted primarily by telephone, but many people, including much of Truman's populist base, did not yet own a telephone. This skewed the data to indicate a stronger support base for Dewey than existed. An unintended and undetected projection error may have contributed to the perception of Truman's bleak chances. The three major polling organizations stopped polling well before the November 2 election date — Roper in September, and Crossley and Gallup in October — thus failing to measure the period when Truman appears to have surged past Dewey.
