One of Peter Robinson's most senior colleagues in government today said he commanded the support of the party.
With church and political figures expressing misgivings following the exposure of his wife Iris's affair with a teenage lover, Sammy Wilson said her indiscretions did not affect the North's First Minister and DUP leader.
Resignation by Mr Robinson could trigger an early Assembly election, Northern Ireland Secretary Shaun Woodward warned.
But Finance Minister Mr Wilson said the leader had done nothing wrong.
"As far as I am concerned he has got support, the stories about Iris don't impugn him," he said as he went to church in north Belfast, where Mr Robinson also attends.
If he falls, the post of First Minister and Deputy First Minister, held by Sinn Féin's Martin McGuinness, would have to be filled.
Sinn Féin could delay nominating unless the DUP agreed to a timescale for the devolution of policing and justice from London to Belfast.
If this was not resolved within seven days it would fall to Mr Woodward to call an election.
He told the Sunday Times: "In those circumstances the Secretary of State is bound by legislation to set a date for election."
Doubts about the future of the beleaguered First Minister intensified today after a close friend of his predecessor suggested he should step down.
The Rev David McIlveen, a Free Presbyterian minister and a confidant of former DUP leader Ian Paisley, said Mr Robinson should consider standing aside temporarily. However, he later clarified that he was not speaking on behalf of Mr Paisley.
It came just hours after his wife Iris was dumped by the party because of her financial dealings with former lover Kirk McCambley.
Mr Robinson has vowed to clear his name after vehemently denying any knowledge of his wife's irregular financial affairs, which if he did know should have been reported to the parliamentary authorities.
Mr Woodward refused to speculate about Mr Robinson's future, but insisted the devolution process was "bigger than one man".
He said: "It is a responsibility on everyone in the Assembly to understand that the consequences of allowing the political process to slide would undoubtedly have an impact on the broader canvas.
"And that if anybody were to be selfish enough to think this is a moment when that can be allowed to be put in the deep freeze, even some may wish to unpick, they would be extremely irresponsible, foolish and would be playing very, very dangerous games."
Mrs Robinson's membership of the DUP has been terminated and she is expected to leave Westminster, Stormont and Castlereagh Borough Council as early as next week.
A party source said: "The next few days is absolutely critical for the party.
"We wanted to show people we were acting decisively. There was no question about it, she had to go and go now.
"There was absolutely no sympathy for the position she found herself in."
East Derry DUP MP Gregory Campbell has said the matter should be resolved within a week after Mr Robinson called in independent lawyers to investigate his conduct.
Mrs Robinson announced over Christmas that she was quitting politics because of severe depression.
But she and her husband have since been plunged into crisis after it emerged that Mrs Robinson had secured £50,000 (€55,614) from two wealthy developers to help her 19-year-old lover Mr McCambley set up a restaurant business in south Belfast.
Today the Metropolitan Tabernacle Church in north Belfast, which Mr Robinson attends, was crammed with people, many no doubt discussing the controversy.
A billboard advertising the church stressed the importance of the family and community - but vandals had scrawled "adulterers" across it with red paint.
Worshipper Jim Daniels, 43, from south Belfast, said: "It might be the end of him, I don't know, everything is happening so fast."