Tuned a full step down. Or standard, just move up two frets.
I've seen Alex play this live, I'm positive it is how it is played.
[ Tab from: http://www.guitaretab.com/g/gaslight-anthem/202174.html ]
d|-------5--------8---7------|
A|-----------5-----------8---|
F|----5----------------------|
C|---------------------------| x 4
G|---------------------------|
D|---------------------------|
There are tabs for the rest of the song this site. Keep in mind all Gaslight Anthem
are tuned a full step down, with the exception of only a few.