Recent polls suggest 70 percent of Democrats support impeachment of President Trump—a preference ignoring obvious lessons from the recent past.

Andrew Johnson was impeached in 1868 during his last months in office and he wasn’t running for re-election. Then with Richard Nixon a century later, momentum against him proved so powerful that he resigned before voters went to the polls for mid-terms.

Only Bill Clinton faced Congressional elections in the midst of an impeachment crisis—and he became the only president since the two-party system began to gain Congressional seats in the middle of his second term. Americans disliked Clinton’s amorous adventures but they hated the idea of impeachment—and still do. If Democrats campaign for Congress promising turmoil, scandal-mongering and gridlock, they will lose—and deserve to lose.