The Lincoln Train, by Maureen McHugh

The Lincoln Train, part of Maureen McHugh's Mothers and Other Monsters collection, got the Hugo for short stories in 1996, and was nominated for the Nebula.  For being a moving story I guess, because the speculation is kind of one-dimensional.  Lincoln is wounded instead of killed when his assassination is attempted, and this changes the policy toward southerners.  But the story is really one of what it is like to be an unwanted refugee, which is by countless accounts horrible.  There is a nice twist in how the protagonist gets help, but for me it's just not developed enough.  Decent, but just two stars from me.