Harvard Law professor Larry Lessig, a longtime critic of big political money, has set the stage for a presidential bid.

It's not your usual White House run, however. He said Tuesday that if he can crowdsource $1 million by Labor Day, he'll leave Harvard and enter the Democratic primaries. He'd be a single-issue candidate, campaigning for a legislative package that would undo restrictive voting laws, make Election Day a national holiday, bar the gerrymandering of congressional districts, and finance elections through public matching funds or vouchers for small donors.

The plan sidesteps the biggest growth area in political money: superPACs and so-called social welfare organizations that raise unlimited sums for "independent" efforts to promote candidates. This unregulated money, some disclosed and some anonymous, is constitutionally protected by recent court decisions, including the Supreme Court's Citizens United ruling in 2010.

If Lessig's goal seems like a long shot, so does his electoral strategy. He would promise to serve as what he calls a "referendum president," making his candidacy a national referendum on the legislation. If he managed to win, he said, "I would serve until Congress passed the statute to fix this rigged system and end the inequality."

Then, job done, he would resign and the vice president would move into the Oval Office.

The trouble with the other candidates, Lessig said, is that they all treat the political money chase as a secondary issue. It's an idea he's been developing for several years. In 2011 he laid out the argument in Republic, Lost. The book tour caught the wave of the Occupy Movement against economic inequality. At an Occupy camp in downtown Washington, Lessig argued that big political donors thwarted open debate by both Occupy and the Tea Party movement.

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