Kefauver launched those hearings because he wanted to rum for the Presidency in 1952--not because he was anti-crime (there were plenty of allegations during his Senate career that he'd taken bribes from various corrupt organizations). Kefauver had the genius to take his subcommittee arund the country--and to have the hearings televised. Those of us (ahem) of a certain age remember the Kefauver hearings because they were televised. They were a sensation: in 1950, they attracted more than 30 million viewers daily--more viewers than there were TV sets in America at the time. Movie theaters, despite their hostility to TV, used to charge people to come in and view the hearings on their big screens.
The most memorable moments came when the committee called Frank Costello, who permitted only his hands to be shown on TV. Asked by the subcommittee counsel if he'd done anything civic-minded in his life, Uncle Frank replied, "I paid my tax." Virginia Hill, Bugsy Siegel's mistress, took the stand, too. Asked by a lascivious-minded subcommittee member how she'd managed to retain the affections of both Siegel and Chicago mob figure Joe Epstein, Hill famously replied: "Haven't you heard? I'm the greatest c**ksucker in America." When the subcommittee finally ended its hearings in '51, Kefauver held a press conference and announced that Abner (Longy) Zwillman, crime boss of Newark, NJ, was the biggest gambling czar in America.
The hearings for the first time alerted millions of Americans that there was such a thing as organized crime, and that it was intimately involved with gambling, especially in Nevada. The hearings led, eventually, to the creation of the Nevada Gaming Commission and the "Black Book." But it took the Valachi hearings in '62 to get the FBI interested in the Mafia.
As for Kefauver, he got nowhere fast in his bid for the Democratic nomination in '52. He did get the Democratic nomination for VP in '56 on Adlai Stevenson's ticket, but they suffered a landslide defeat.