My source on that is Mazzocchi--at the time he was working as OCAW Leg. Dir.
The 95th Congress ('77-'79) Senate consisted of 61 Democrats, 38 Repubs & 1 independent. The House was 292 Dems and 143 Repubs.
As we know, 60 are needed in the Senate to defeat a filibuster, which was mounted against the weak labor law reform in question, which had passed 257-163 in the House in 1977. It was filibustered in the Senate, and although there were 61 sitting Democrats, it failed, since only 58 would vote to end the filibuster.
I think during that same Congress the construction trades tried to reform common situs picketing and couldn't get anything through, either (Ford had vetoed a bill earlier). I know a postalworker who says watching the Carter admin. made him a socialist.
Cue Nathan to tell us how none of this should really reflect badly on the Democrats, though.
Jenny Brown