At a County Fair I think she'd do pretty well. At an APA Sanctioned Show that judges based on the Standard, I'm sorry, she would not do well at all. Most Rhode Island Reds out there are bred solely for Production, so, it causes their color to fade, their bodies to shrink and become lanky, and their dual purpose cease to exist.
The birds shown above my post are what they should look like - But, again, at most County Fairs people just show for the fun, so she should be fine there!
Edited to Add - I don't think you have a Red though. Her legs look slate or white, I think she's a mutt. I'm so sorry to tell you!
First your Hen is a Production Red and not a Rhode Island Red, not is would all depend on how strict and how though the competition at your County Fair is.
At the County Fairs I go to, I hate to say your hen would not do very well they go by APA rules and the competition is strong and most of the guys either show, shown, will be showing at Ohio Nationals.
Some of my Reds -
Rose Comb Rooster --
Rose Comb Hen (just before molt sorry about the bad feathers) --