Stephen Fry, who is currently working on a film of the book in New Zealand, tweeted on Tuesday: “Honestly, @saveTheHobbit, sometimes I'm ashamed of the business I'm in. What pointless, self-defeating bullying."
They want the pub in Southampton, which serves cocktails named after characters in the JRR Tolkien book such as 'Frodo' and 'Gandalf', to choose another name.
But now Gandalf himself, Sir Ian, has lent his support to let the pub, reports the Daily Telegraph.
The 72-year-old actor wrote on his Website: "Gandalf's portrait hangs outside The Hobbit pub ... and has done for the last 20 years and more. I haven't been there but it's clearly not a place to ill-treat hobbits, elves, dwarves and wizards, in any way. So what's the problem?
He goes on: "I am a part-landlord of a pub called The Grapes. So far no vintners' group has objected. That would be silly of course. As is this unnecessary pettiness. More Alice's Wonderland than Tolkien's Middle-earth. Harrumph.
"I haven't yet talked to Stephen Fry about his disapproval of this Hollywood bullying but I'm with him all the way. All the way to The Hobbit pub once filming is over in July."
A Save the Hobbit Facebook page was set up a week ago by student Heather Cartwright from Southampton University and has attracted massive support with 50,000 likes and counting.
But last night, it emerged that the Saul Zaentz Company (SZC) threatening the public house wanted to resolve the matter amicably.
Save the Hobbit campaigners said: "The SZC wishes to avoid a lengthy court battle with Punch Taverns.
"They have asked that we arrange to operate by way of License and that they would grant this License for a nominal fee of $100 (£63) per annum."
It continued: "Just to clarify, the fight for The Hobbit is NOT over yet; more detail to come from Stella soon. Good work, and keep spreading the word."