What is the lesson learned from the WIsconsin election result? That Democratic leaders should not assume that their voters are knee-jerk pro-public sector union.  17% of pro Scott Walker voters said in exit polling that they support President Obama, but only 6% of anti-Scott Walker voters said they are supporting Mitt Romney. 

Deval Patrick and Democratic House and Senate leaders in Massachusetts showed with their support for municipal health care reform last year that it is possible for Democrats to do right by the public (in that case, schoolchildren) even when it means bucking the unions. If Democrats did more of that, they'd probably win over more voters.