Astute comparison. In 1864, Lincoln was feeling so much heat over the casualties (and, compared to Iraq, a single DAY during the Civil War had more casualties than our two WARS in Iraq), that he was not expected to win re-nomination from his own party. The Dems hated him. (What's new). His own limp-wristed "moderates" were ready to desert him, and the "far-right" wing (Radicals) wanted someone more, er, radical.
But the military victories came in the fall of 1864, and that was that. Chances are, Bush will benefit from several good developments on the battlefield (and in the economy) by the fall of 2004 as well.