No it cannot.
I ran GTX260 on a CM460W eXtreme and it just ran fine till 2 hours , and after that started giving trouble, Instant restarts, shutdowns etc.
however, changing the PSU to just CM500W solved this problem.
You should consider getting a better PSU first THEN buy a better GPU.
Find a Corsair CX400 or a CM500W (least recommended)... both are at same price and have same specs, but I prefer CX400. YOu will have to find it hard but its your only GOOD choice as per Budget user.