Those wealthy donors were the Tiffany's (Jewler's) Two Colt 1895s in 7x57mm Mauser. They only had about 1000 rds of 7mm ammo when they went a shore. Not much for an automatic belt fed machine gun, much less 2 guns. Later they would capture 7x57 ammo from the Spaniards. With enough ammo now, they were able to support the attacks up San Juan and Kettle hills. Besides the Brownings were a couple of the last 45-70 Gatling Guns on wheeled carriages. Last time Gatling guns (manual) would be used in combat.
During the Spanish American War, 3 Regiments of Volunteer Calvary were formed. 1st, 2nd and 3rd USVC for overseas deployment. These were unorganized mounted militia called up, armed and trained for service. Only the 1st saw action and deployment. Believe 2nd and 3rd stayed in the US. The 1st was commanded by COL Leonard Wood. LTC Roosevelt was his deputy. However, Teddy took command of the 1st when they went ashore in Cuba. So, if anyone ever mentions the militia part of the 2A. There you go with full auto weapons, paid by civilians for civilians.
CD