Ian Welsh re-posted an article he wrote in 2007 when JRE was running hard against now-President Zero and now Secretary of State Clinton. The central thesis is that JRE recognized early that union-strong districts tend to Democratic and when Democrats get their support, they tend to win---precisely the thing Republicans and Corporate-persons have known for 40 years and spent lots of money and time trying to destroy. And for the most part, they have destroyed that connection.
So Ian raises the rather specific point that unions are the one thing Republicans fear and isn't it strange Dems don't won't to support them rather than assist in undermining them?
It's a fair question. And it is also a fair observation that unions too aren't so "unified" anymore when it comes to concentrating their remaining political clout effectively (recall the SEIU debates),
http://www.ianwelsh.net/user-when-labor-is-strong-democrats-win…/