The possibility of payback in such forms as the following will be the continuing story:

That news comes courtesy of federal disclosure forms that unions file each year with the Department of Labor. The Bush Administration toughened the enforcement of those disclosure rules, but under pressure from unions the Obama Labor shop is slashing funding for such enforcement. Without such disclosure, workers wouldn’t be able to see how their union chiefs are managing their mandatory dues money.

But there’s a more fundamental, and more interesting, angle (emphasis added):

An SEIU spokeswoman says the union works on a four-year cycle, in which it goes “all out for the presidential election” and then rebuilds its finances. She adds the union has paid back more than $10 million of the $25 million it borrowed last year. But it’s nonetheless true that the SEIU’s liabilities have continued to climb each year from 2003 to 2008.

In that regard, there doesn’t appear to be much difference between a labor union and a charitable organization that undertakes a remunerative enterprise (selling something or offering services) to raise money for the cause that represents its reason for being. The worker representation by which the unions raise their money is a means of financing political activism. Which side of the organizations represents their core purpose is probably not as easy a question to answer as it ought to be.