While rank and file members had no input in early nominations , they were still drawn by the aura of mystery surrounding the convention , and networks began to broadcast speeches and debates to the general public . NBC affiliate W2XBS in New York City made the first telecast of a national party convention , of the 1940 Republican National Convention in Philadelphia , Pennsylvania , and the other two of the Big Three television networks soon followed . As NBC News anchorman John Chancellor stated just before the start of the 1972 Democratic National Convention , " convention coverage is the most important thing we do . The conventions are not just political theater , but really serious stuff , and that 's why all the networks have an obligation to give gavel-to-gavel coverage . It 's a time when we all ought to be doing our duty "
1972 Democratic National Convention
1972 Democratic National Convention
United States presidential nominating convention