Both are correct
This is probably beating a dead horse, but "Was" and "Were" both express the imperfect of "To Be" and the table looks like this:
Sing Plur
I was We were
You were YOU were
He, She, It was They were
Numerically, "Was" is appropriate only in the first and third person singular and "Were" is appropriate everywhere else.
However, as it has been pointed out when you are expressing potential action, it is common to use "Were" regardless of number