Supporter adjectives are listed in this post. Each word below can often be found in front of the noun supporter in the same sentence. This reference page can help answer the question what are some adjectives commonly used for describing SUPPORTER.
able, active, ardent, athletic, avid, avowed, best, big, biggest, chief, committed, consistent
constant, convinced, cordial, devoted, early, earnest, effective, efficient, energetic, enthusiastic, faithful, fervent
financial, firm, former, generous, great, greatest, hearty, important, influential, keen, key, leading
liberal, lifelong, longtime, loyal, main, major, old, only, outspoken, passionate, political, powerful
principal, prominent, single, sole, stalwart, stanch, staunch, staunchest, steadfast, steady, strenuous, strong
strongest, time, vigorous, vocal, warm, zealous
Hope this word list had the adjective used with supporter you were looking for. Additional describing words / adjectives that describe / adjectives of various nouns can be found in the other pages on this website.