Hmmm, there is a whole lot I didn't like in this article but for your reading pleasure, here it is.
Though President Obama carefully cultivated the majority-minority labor coalition as a candidate, he has not been the staunch ally many of them supposed he would be. The Affordable Care Act, lobbied into law by a coalition that included unions, might well undermine the concept of the 40-hour week and doesn't provide subsidies to unions who fund their health plans through trust funds. With the exception of the United Auto Workers, labor unions cringed at the 2009 bank bailout because it was not accompanied by much help at all for state and local governments. The president's student loan compromise with Republicans bucked labor demands that he fight for a better, longer-lasting bill.

Now, labor is again making noises about sitting out the election. Unions are still the biggest and most concentrated source of money and volunteers for Democrats. Years go, I asked Andrew Stern, then the president of SEIU, whether labor would simply stop contributing money and boots on the ground to candidates for federal office as a show of displeasure. I don't remember his exact response, but he said something along the lines of hoping that things never got that bleak. In some ways, though, it may be the only card that labor has yet to play. They may never play it, because it would seal in their own irrelevance, especially if the Democrats figured out how to find foot soldiers and "soft money" without them. In fact, the Democratic Party does seem to realize that labor might not be around forever; increasingly, the corporate sector is replacing core labor financial functions within the party's division of labor.
Unions need to take a page from the Tea Party - The Week