Stored 900S 1997 Won't Start

I stored my 1997 900S non-turbo for about a year in my garage. This past week, I've been trying to get it started. The battery was dead, so purchased a new one today.. The car will turnover, but very slow. It acts like the battery is dead. I've even used jumper cables from my truck to the new battery and the car is still turning over very slow. Any ideas as to what I should do? The car was running fine when I parked it last year... thanks Dan S.

any chance some critters could have gotten into the undercarriage and wiring?