Law professor Lawrence Lessig dropped his campaign for the Democratic nomination Tuesday.

Who?

Lessig is an activist for campaign-financing reform, and he based his entire presidential race around two ideas. First, as he said in his farewell video, he claimed that nothing can be done about issues Democrats care about unless the way campaigns are financed changes. Second, he said that if he had been elected based on this one issue, he would have had a voter mandate, and Congress would have had no choice but to pass the reforms he wanted.

Vox's Dylan Matthews nails Lessig's first contention in a tweet: "The entire central organizing premise for Lessig2016 was ridiculous. Of course you can get important stuff done [without] campaign finance reform."

Yup. True, many liberals were disappointed in what they saw as compromises in Obamacare, the economic stimulus, the Dodd- Frank financial reform package, the president's executive action on immigration and climate, and all of the other changes in federal policy over the last seven years. But one has to be far from the U.S. mainstream to believe that nothing significant happened, especially in the two years Barack Obama had a Democratic Congress.

Moreover, congressional capacity is limited. Had the 111th Congress (2009-2010) focused on campaign finance and similar policies involving the political process, it would have had to give up legislation that it passed in other areas.

And no matter what Lessig says about a mandate from voters, Republicans in Congress would have remained free to ignore his proposed legislation. Voters also would have elected those Republicans, who would have had no reason to give more weight to the president's electorate.

Lessig complained that the Democrats excluded him from their debates. If true, good for them. Republicans should have taken tighter control of theirs, too. Remember, dozens of people "run" for president every cycle — people none of us ever hear about, but who nevertheless enter at least one primary. Lessig never gave anyone reason to believe he belonged in the "major candidate" category. He didn't have conventional qualifications for the job and made no pretense of interest in being president. There's no reason parties should elevate issue activism to the national debate platform.

If Lessig wants to move his issue to the top of the Democratic agenda, there are other ways to do that. His brief "candidacy" only hurt the cause he claims to care about — as was easy to predict from the outset.