A real bad Undergrad GPA

So, here it goes. I'm a Bio major at the College of the Holy Cross. I ended my Junior year with a 2.28 gpa. Yes, a 2.28. No failures, my lowest grade was a C-. Tons of C's. I'm weighing out my options here. If I bring it up to a 2.5 by graduation, I was wondering what else I could do...

I am aware of the grade replacement policy. What if I did that with most of the Cs? Would that work?
Thanks,
Rob