Here at the Volokh Conspiracy, we make a point of informing our readers about all the really important issues of our time. Thus, I was distressed to learn from the comments about my post criticizing the analogy between John McCain and Gandalf that many of our learned readers don't know what happened to Radagast the Brown, the third wizard mentioned by name in The Lord of The Rings. As LOTR fans know, Gandalf, Saruman, and Radagast were three of the five Wizards (known as the Istari) sent by the Valar to help the Elves and Men of Middle Earth battle Sauron. Unlike that of Gandalf and Saruman, Radagast's ultimate fate is not discussed in LOTR.
Fortunately, J.R.R. Tolkien informed us of what happened to him in his later essay, "The Istari,"(excerpted here):
Indeed, of all the Istari, one only remained faithful, and he was the last-comer. For Radagast, the fourth, became enamoured of the many beasts and birds that dwelt in Middle-earth, and forsook Elves and Men, and spent his days among the wild creatures.
It's not entirely clear whether Radagast stayed among the "beasts and birds" of Middle Earth forever, or whether the Valar eventually forgave him for his (partial) failure and allowed him to return home to Valinor.
Commenters on the previous post proposed various modern politicians as analogues to Radagast. One possible one is Fred Thompson, the preferred presidential candidate of many of my fellow Conspirators. Thompson's heart, like Radagast's, may have been in the right place; but he too had no real enthusiasm for his mission, and soon dropped out of the race without ever having made much of an effort. Whether Thompson deserves the abuse hurled at Radagast by Saruman ("Radagast the Bird-tamer! Radagast the Simple! Radagast the Fool! Yet he had just the wit to play the part that I set him..."), is left as an exercise for the reader.
As for the other two Istari, Alatar and Pallando, Tolkien gave contradictory indications as to their ultimate fate, but probably they failed even more completely than Radagast.