Who Wields Magic?
The first thing to understand with The Lord of the Rings magic system is that Middle Earth is not Earth. Yes, Tolkien was essentially creating a mythology for England. However, magic seems to be ever-presents in Middle Earth in a way that it is not in the real world. Mount Doom, the volcano, is the only place that can destroy The One Ring. No one made Mount Doom into a magical volcano. It just is. The very existence of Smaug, the barrow wights, and trolls that turn to stone in the sun give an intrinsic sense of magic to Middle Earth.
The primary conscious wielders of magic are, of course, wizards. Called Maiar in older tongues, they are actually primordial spirits who helped shape the world. In the Third Age (the era in which The Hobbit and The Lord of the Rings take place), exactly five of them have taken humanoid form as wizards. That right there tells you that everything about them is magical. They command the elements, can whisper or shout words of power, create orcs, and so much more. As a soft magic system, there is never really a limit places on the power of wizards like Gandalf or Saruman. There is also no specific system in place that governs how or when they use their magical abilities.
Elves, particularly high elves like Galadriel and Elrond, also have some magical power. Some of that may come from their use of Sauron’s rings, but some is intrinsic. Galadriel used a mirror to look into the past and future. Elrond was known as a great healer, and even called upon a river to wash away the Nazgul. Many elvish smiths seemed to wield magic as well, imbuing magical powers into their works like how Sting glowed when near goblins.
Notice a word that has come up twice now. Intrinsic. Tolkien did seem to lean into magic as part of nature, and therefore, certain species and beings had more access to magic because of who they are. Tom Bombadil, one of the most controversial characters in Tolkien’s work, is possibly the embodiment of nature. Perhaps he stands in for God. No one is certain. But he seems intrinsically linked to Middle Earth itself, and displays some of the greatest and easiest magic in the story.
There are others that use a little magic, as well. Sauron, of course, is a powerful Maiar like Gandalf. Men with blood of the First Men had some limited magical abilities, including prolonged life. Those with royal blood were shown to have magic tied to their bloodlines, such as Isildur, who cursed the Dead Men of Dunharrow to remain in Middle Earth until called upon.