Daniel Henninger of the Wall Street Journal devotes a “Wonder Land” column to a reconsideration of an old political insult.

A constant of political life has been that there is only one “stupid party” in America—the Republican Party. Then one day you get out of bed, look out the window and what do you see? Democrats. The Democrats are turning themselves into the new stupid party of American politics.

In the liberal pundits’ telling, Republicans are the party of the yahoo heartland, the anti-abortion religious right and the anti-government tea party. The stupid party.

Of course this is a caricature. Besides, none of this bad-mouthing matters unless too many average voters conclude that a weird political fringe now represents the party’s core.

Which brings us to the Draft Elizabeth Warren movement.

Last week more than 300 former Obama staffers signed an open letter urging the famous Harvard Law School professor to run in 2016. Days earlier, two big progressive groups, MoveOn.org and Democracy for America, also pressed the first-term Massachusetts senator to seek the party’s presidential nomination.

The implicit logic of the Draft Warren movement is that after eight years of the Obama presidency, the American people want to move . . . further left.

However intriguing that proposition, the real problem for the political pros behind Draft Warren or even the Ready for Hillary super PAC is that the Democratic left’s high-publicity wing insists on doing stupid things in public that turn off more voters than they turn on.