United Future leader Peter Dunne said today Mr Graf had been totally up front about his past.
"He did the crime and served his time, but he has gone on to contribute immensely and passionately to the public good, particularly with his work as an anti-1080 campaigner," Mr Dunne said.
"We are very proud to have him on board and we know he is a good man and a good candidate, and we believe that people will take him for that."
Mr Dunne said people should be allowed to contribute, and no one should be written off for "one mistake".
United Future party president Judy Turner, in a statement today announcing Mr Graf's candidacy said he would make a very strong candidate "because many people on the West Coast strongly identify with the anti-1080 cause and Clyde is almost legendary in his work against the use of this destructive poison".
"Clyde is a passionate New Zealander who has really laid it on the line to fight 1080, and he will give West Coasters the chance to send a real message to Parliament."
He has been ranked at No 11 on the party list, which is headed by Mr Dunne.
When asked today about his past, Mr Graf said he definitely had life experience.
"Also, over the last couple of years, it has helped to harden my skin and I've become more tolerant of negative comments. They don't hurt so much."
United Future previously announced Hokitika anti-1080 activist Jackie Douglas as its West Coast-Tasman candidate after Mr Dunne visited the West Coast, but she suddenly withdrew her nomination about two weeks later.
The party's media statement today announcing the party list was titled "Credibility and experience top United Future list".
The Electoral Commission confirmed that Mr Graf was eligible to stand under current rules.
