This story is from Military.com by Blake Stilwell:

Few U.S. elections were more contentious and controversial than the one in 1864. Looking back at more than 100 years of history since, it might be difficult to imagine any outcome other than Abraham Lincoln winning in a landslide election.

But it was the votes of U.S. troops that put Lincoln over the top and forever changed the way Americans at war vote in elections.

In 1864, the future of the presidency wasn’t certain. Lincoln was facing a re-election battle that seemed as brutal as the Union victory at Antietam just two years earlier — and he was facing the architect of that victory, Gen. George B. McClellan.

Read the full story here.