With House Speaker Nancy Pelosi having decided to move forward on impeachment, many Republicans and conservative commentators have been outwardly giddy. This will be a disaster for Democrats, they argue, because polls have shown impeachment is immensely unpopular.

The move may end up proving unpopular, but Republicans cannot make that assumption at this point, because the polling we have on impeachment is dated and does not reflect the fast-moving developments of the Ukraine story.