cleaning a hat

I bought my husband a Stetson hat on sale a few years ago. He hasn't worn it much but likes it a lot for certain occaisions. The trouble is, it has gotten dirty. It is made of some kind of khaki fabric which is stiff and blocked. We don't have any kind of a place that can clean a hat anywhere within driving distance of us, so I have to clean it myself. Foam carpet cleaner has crossed my mind, lol. But who knows, it might work.
On the other hand I vaguely remember a cleaner called Energine from years ago. I think it was supposed to be a dry-cleaning fluid. I don't know if it's still around of if there is a better product now.
Any suggestions would be appreciated...Betty