are you checking bags? if so, that's cutting it really close. i've had experiences where it takes 20-25 minutes to get from the marc station to the terminal. i'm heading up there from union station thursday for a 1:20pm flight, and i'm taking the 11:15 train to BWI. get in at 11:45. that's probably about as close as i would recommend. an hour? cutting close IMO.

and yes, there are cabs. i would probably recommend that. i think it's like $15, but i've never done it so i couldn't tell you.