Deputy First Minister Nicola Sturgeon, Scottish Green Party co-convenor Patrick Harvie and senior Labour Party councillor Stephen Curran have all offered support for the signage to be retained, while a local campaign has emerged to demand the Cessnock sign stays.
The sign is an ornate fusion of the styles of architectural masters Alexander "Greek" Thomson and Charles Rennie Mackintosh.
But the removal of the metal signage from the station next to Paisley Road West on the city's south side has created such a stir the organisation which runs the Subway has halted work on uprooting a second archway.
One of the arches has already been removed and put in storage, with a potential new home to be found within Glasgow's new transport museum.
But, while refusing to commit to keeping the remaining archway, Strathclyde Partnership for Transport said it had now commenced discussions with Glasgow City Council to see if any solution can be found.
The two metal arches were erected at the Cessnock Subway entrances in 1989, their design a deliberate pastiche of Greek Thomson and Mackintosh given the proximity of some landmark buildings designed by the pair. They had been installed as part of a general clean up of the Cessnock area and annually greet hundreds of thousands heading to Ibrox Stadium and the Glasgow Science Centre.
With the Subway going through a cosmetic makeover in the run-up to the 2014 Commonwealth Games and SPT seeking to roll out a uniform branding at all stations, work began to remove the arches last Friday.
However, the railings around the stations are now adorned with signs demanding the return of the arch.
Meanwhile, Ms Sturgeon, the local MSP, when asked on social media platform Twitter if she supported the campaign, said: "Yes, 100%. Cessnock Subway sign should stay."
Tory councillor David Meikle said: "I don't understand this decision. Outrageous. I urge SPT to reinstate the sign."
Support also came from Labour candidate for Govan in 2011 and the city council's education spokesman Stephen Curran, who said: "It would be a real shame to lose (the sign)."
SPT said the new signage and removal of the old had been given full planning permission last year, with no heritage issues arising, and that the new branding "will help anyone wanting to travel underground, to identify the Subway quickly and easily and in turn, encourage more people to use it".
A spokeswoman added: "That does not mean we will forget our heritage. Many elements of the 1970s design will be preserved and we are endeavouring to capture as much of that as possible during the upgrade.
"Pieces of significance are being stored and we are in discussion with the Riverside Museum and others about how people might enjoy these again in future. The Cessnock metal arches are part of that preservation strategy. Despite the fact they may not be considered as architecturally significant we do appreciate that they have been a key part of the area since 1989."