Bombadil: One of the Blue Wizards?

[leapofberen]

Bombadil aside, Tolkien reckoned that the Blue Wizards fell as Saruman did in one of his many letters (211 in Letters, though perhaps he was not certain...

[They were as] Missionaries to enemy occupied lands as it were [the far East of ME]. What success they had I do not know; but I fear that they failed, as Saruman did, though doubtless in different ways; and I suspect they were founders or beginners of secret cults and "magic" traditions that outlasted the fall of Sauron.

That seems to run awry of the nature of Bombadil, both within LOTR and Tolkien's other letters. Not to mention the extreme geographic differences of the Blue Wizards and Bombadil throughout the Third Age.

From a completely personal pov, I obtain the sense that Bombadil is simply too ancient, unaffected, earthy and aloof to have been one of the Istari sent to Middle Earth. Besides, Gandalf goes to see him at the end of The Return stating that while he has been a stone doomed to roll, Bombadil has been a quote:

moss gatherer...but my rolling days are ending, and now we shall have much to say to one another.

This seems to say to me that Gandalf held Bombadil in a regard unlike that of the other Istari anyhow.