Which is correct "broad-base" or "broad-based" in the sentence:
Parents, teachers, principals, senior citizens, and local businesses are all represented in a "broad-base" coalition supporting this proposal.
You'll see nouns and adjectives used there. This sounds to me like a coalition that has come into existence for this proposal. If so, I'd use 'based', while if it's a more permanent coalition, I'd be more likely to use the noun.