According to C.E. Hooper, Inc. on November 2nd, 1948 -- Election Night -- 74.1% of television households in New York City were watching election coverage between 9PM and 11PM on one of five stations . Here are the specifics:
Station Rating WNBT: 32.3 WJZ: 15.0 WABD: 13.6 WCBS: 8.2 WPIX: 5.0
Before reporting Hooper's ratings for radio and television, The New York Times noted "Should anyone still believe in polls," referring to the now infamous upset that saw incumbent Harry S. Truman defeat heavily favored Thomas E. Dewey.
1 "Radio and Television." New York Times. 4 Nov. 1948: 58.