Coulter dismissed Democratic electoral gains as "pathetic" by historical standards -- is she right?

In her syndicated column, Ann Coulter claimed that the Democratic Party made "pathetic gains" in the November 7 midterm elections. In fact, the Democrats' gains in the House are just slightly under the average for the party out of power in the White House in the sixth-year midterm elections over the past century, and the Democrats' Senate gains are above the average. Moreover, the 2006 elections were the first sixth-year midterms since 1918 in which control of both houses of Congress switched parties.