Ayr, like everywhere in Ayrshire, is absolutely riddled with Rangers fans. Wouldn't even say 'Old Firm' fans, it is just absolutely riddled by braindead Rangers 'fans' who take as much pleasure in Ayr getting beat as they do in Rangers winning.
Ayr United's core fanbase is obviously Ayr and surrounding South Ayrshire. Anything from Girvan up to Troon is mostly Ayr (outside the OF) but Troon itself is a bit mixed between Ayr and Killie although it lies in South Ayrshire.
Aside from that, the Aberdeen AUSC Quiz Night on Friday was seemingly mobbed, with a flag on the wall reading 'Kuala Lumpur - Ayr United' so Kerrball is evidently going global.