Would Gandalf

[lathspell]

The Valar did not interfere with Melkor themselves. They sent their Maiar to take care of it, with Eonwë as their leader. They did not do this, because it just popped in their minds that... oh, yeah, Melkor still walks around somewhere, let's do something about it. No, They were persuaded by Eärendil's speech which he made before Manwë's throne. Tolkien mentions in the Silmarillion that only Eärendil and only at that time he could make such a speech that mastered the Ainur's minds. Personally I believe the Silmaril helped a lot. So the Ainur would not come, because there would be none to tell them the need.

Maybe Gandalf would challenge Sauron, but he would have lost. The Ring would have been found be Sauron's servants one day if Gollum took it for himself. No matter how you see it... if the Ring wasn't destroyed by Frodo, M-e would be Dark again.

greetings,
lathspell