The Liberal Democrat who mounted the legal challenge against former immigration minister Phil Woolas said he "risked everything" to seek justice.
Mr Woolas was stripped of his Oldham and Saddleworth seat for lying about his opponent Elwyn Watkins on campaign leaflets.
Speaking to the BBC, Mr Watkins said "politics needed to be cleaned up".
The High Court has rejected Mr Woolas' request for a judicial review of the election court's ruling.
In his first interview since the election court ruled in his favour, Mr Watkins said many people thought he was "crazy" and that he had "little chance of success" in proving Mr Woolas had repeatedly and knowingly lied about him.
It is the first time in 99 years that the specially convened election court - which has to be held in the disputed constituency - has ruled in the claimant's favour.
The two judges barred Mr Woolas from standing for elected office for three years ruling he was guilty of breaching the Representation of the People Act 1983 by making false statements.
Mr Watkins claimed his Labour opponent knowingly misled voters in Oldham East in a bid to stir up religious tensions in the last days of the election by claiming the Lib Dem member had "wooed" Islamic extremists.
When he first told his lawyers that he was planning to take legal action against his opponent, Mr Watkins said they "rolled their eyes" at him.
"I was prepared to risk my financial future," he explained, "I told them I would rather fight this and lose than walk away and always regret not having stood up for something that I thought was wrong."
He said that shortly before the General Election when voters were inundated with leaflets from the local Labour Party claiming he was wooing extremists, even his mother questioned him about the claims.
"Like any mother she wanted to come out and help us run the campaign. She came in and saw the leaflets.
"She said it was disgusting but then she said, 'it's not true is it?'.
"That's my own mother who loves me dearly and probably has a reasonable opinion of me. But if you print things some people will think that there is some truth in it."
Mr Watkins said he was not frustrated by Mr Woolas' attempts to secure a judicial review against the ruling, but he wanted to see a by-election "as soon as possible".
"We are ready for the by-election, I am yet to meet anybody who thinks Mr Woolas would be able to change the decision of the court last week.
"Clearly it's not an ideal situation, they (Oldham East Saddleworth constituents) don't have an MP to fight for them and champion their causes.
"The legal procedure needs to take its course but I just hope it doesn't take too long because they need an MP to fight their corner in parliament."
House of Commons speaker John Bercow said it was "settled law" that the decisions of High Court judges sitting in their capacity as High Court judges "cannot be subject of applications for judicial review".
But he said Mr Woolas could now apply to the Court of Appeal.