Well it depends, what does the rest of your application look like? Are you sure you can not pull up a couple of these grades with Finals or other assignments, you must be able to pull at least one if not 2 of the grades up before the end. If the rest of your application is awesome then go for it.
Also think why are you doing poorly in these courses....
That is a hard choice, I think I would go for it, I would not want to wait another year if I thought i had a competitive application outside of those grades. Also it depends on where you are applying. Some schools hate to see multiple Cs.