Main character. Was the 26th President of the United States, but now is the pilot of GIANT ROBOT EL PRESIDENTE. Brought back to life by Niels Bohr in his secret lab, and now does the sorts of things that you'd expect a reincarnated politician from the early 20th-century to do... which surprisingly isn't that different from the average modern-day person.

Giant robot invented by Niels Bohr, and main vehicle of Theodore Roosevelt. Modeled after Theodore Roosevelt, and has a few powers and attacks with that theme in mind. Powered by the secrets of quantum mechanics (in other words, nobody really knows).

Danish physicist / scientist and inventor / mechanic of GIANT ROBOT EL PRESIDENTE. How he's still alive after his death in 1962, I have no idea, but does that really matter? Just ignore that for the sake of plot continuity. Uses his connections to gain corporate sponsors to fund his secret lab and the production of El Presidente, and brought back Teddy Roosevelt to be its pilot. Why Teddy Roosevelt, I have no idea either.

Was William Howard Taft in the past, but after a bizarre mishap involving candy, overeating, and a toxic spill he has now become T-FAT, arch-enemy of Theodore Roosevelt. Don't get between him and his food, if you know what's good for your health...