Colin Hamilton, 68, needed an operation after a dog locked on to his fingers while he was delivering leaflets in Gilmerton.
The retired teacher was campaigning for Labour candidate Ian Murray in Edinburgh South when he was hurt in Peveril Terrace yesterday afternoon.
Mr Hamilton had been pushing literature through the stiff brush draught excluder of a letterbox when a vicious canine on the other side of the door jumped up and clamped its jaws around the fingers of his right hand – slicing down to his bone.
Dazed, losing blood and close to fainting, Mr Hamilton staggered on to the street and was eventually helped by a couple who called an ambulance.
The pensioner, from Morningside, was rushed to Edinburgh Royal Infirmary and later transferred to St John’s Hospital in Livingston to undergo surgery.
Mr Hamilton’s daughter, Gwen, said her committed dad had already phoned Mr Murray’s office to apologise for being unable to deliver leaflets for the rest of the day – while optimistically insisting he could be back on the campaign trail for the final push.
Speaking to the Evening News from accident and emergency, Mr Hamilton said: “It just happened instantaneously. I felt the pain and then I could hear the bark. It held on to my fingers for a moment and then it let go.
“One of my fingers on my right hand has been bitten down to the bone. The middle finger is the bad one – and the index finger. Unfortunately it got under the nail and it’s ripped half the nail off.”
Mr Murray, who is currently fighting to win back his former seat, said: “Colin has delivered thousands and thousands of leaflets for us – he is one of our leafleting stalwarts.
“It’s an awful thing to happen and I hope he is better soon.”
Police said the incident had been reported to them by ambulance crews, but said Mr Hamilton did not want to make a complaint.