Daniel Greenwood has posted this draft on SSRN.  Here is the abstract:

This Article proposes several routes to reverse Citizens United, the Supreme Court case holding that corporate campaign spending is “speech” protected by the First Amendment.

The core problem of Citizens United is that corporations are illegitimate participants in our politics. Corporate law requires corporate officers to pursue the corporate interest. They are thus disqualified from considering the central political questions of a democratic capitalist country: defining the rules of the market (which define corporate interests) and balancing profit against other, more important, values. The high road to fixing Citizens United is a constitutional amendment to extend the fundamental insights of the Eighteenth Century liberal revolutions to the corporate sector: the Constitution should protect us from corporate officers, not the other way around.

But we can also reform Citizens United by statute. Citizens United is based on a conceptual error: Corporate “speech” is an issue of corporate governance, not the First Amendment. Even if we entirely banned corporate electioneering and lobbying, every corporate employee, investor and customer would remain entirely free to speak, spend and unite to promote political positions. Instead, the issue is corporate governance – for whom corporate officials work and the limits on the authority they are given to use money that is not their own.

No constitutional amendment is necessary. Congress or even a single state could require a corporation which opts to electioneer to do so in accord with our constitutional values of free debate and democratic elections.