Yep, I used to use 91% Isopropyl to clean track, but after reading that it has a high Dielectric constant, I switched to using Low-Odor Mineral Spirits. While effective, alcohol seems to require more frequent track cleaning because of the higher resistance its residue leaves on the track. Higher resistance leads to more carbon deposits on the rails. Some recommend No-Ox, but I haven't tried it since it's a dielectric grease that needs to be thoroughly wiped off after application.
As Pat says, Lighter Fluid works well too.
Here's a chart of Polar Solvents. I think it was @gunrunnerjohn who posted this.