Labor union membership, which had fought for wage increases and formed a backbone of the Democratic coalition during the good-times economy (1948-1973) Question 10 options: has expanded to almost 50% of the private sector workforce has been unable to make any appreciable gains in membership in the past 50 years lost most of its members when it decided to saddle up to the Democratic party has shrunk from over a third of the private sector's workforce (1950s) to less than 10 percent