JOEL KOTKIN: The Three-Headed Democratic Party:

As they face the midterm elections with the wind in their faces, Democrats increasingly stake their collective political future on the issue of inequality. The topic has great resonance, given the economy’s vast preponderance of benefits to the very rich and the almost obsessive focus on the issue by the mainstream media.

But if raising the class-warfare flag gives Democrats at least hope for avoiding a 2010-style shellacking, it also threatens to open up huge, and potentially irreconcilable, differences within the party. Unlike with social issues, where the party is relatively united, class divides threaten party unity by pitting its different constituencies against each other.

Today we can speak really of three Democratic parties, each with a separate class interest. Their divisions are as deep, perhaps more so, as that between the mainstream Republican Party and the Tea Party. As the Republicans are divided between Main Street grass-roots activists and the corporate “moderate” wing, the Democrats face potential schisms over a whole series of policies, from policing Wall Street to the environment, monetary policy and energy.

The GOP, with an increased focus on economic opportunity, could peel away a lot of these votes, especially if it is able to overcome its reflexive horror at attacking big business.