Keg beer has been warm for about 5 days, is it still good?

I got a keg on Saturday for a party and its probably about 1/3 full now. The keg was chilled only for that day and now has been at room temparature for 5 days. Will it still taste good if I re-chill it? I doubt it makes a difference but the beer is Redhook Longhammer ale.