Just got back from Boston. Feel like I did a middling to bad job on that interview. I was tired, hungover, just not feeling it. Unfortunately the further along I got into the day, the more interested I was in the job and the more it seemed like a great fit. I figured all of this out too late, though. :(
Write them a letter/email explaining this. They will hopefully view you in a more empathetic, positive framework. Sounds as if you have nothing to lose, only a chance to be there in an even better position than your current one.
Dear Prospective Employer,Thank you for the opportunity to interview with your firm. I was not completely sold on this job going in, so I went ahead and got fit-shaced the night before. You may have noticed I was a bit hung over early in the day (I didn't call anyone a dickmitten, did I?), but did you see how I rallied in the afternoon? That's gotta count for something, right?! Rest assured, this will probably not happen too often once you hire me. As my good friends from the innernets can attest, I am very reliable. I think you will find my references to be impeccable, though be forewarned that Julio's messages can be a little confusing at first. Looking forward to the next round of interviews.YIC,K