Nadine Dorries has warned the Prime Minister he could face a leadership challenge if the Government's policies don't change.
Today she told ITV News, the Government has been going in completely the wrong direction and needed to change tack.
But Dorries also insisted she was not against modernisation.
She also said that if the party went into next year's county council elections in the same position then there would be many MPs getting restless with Mr Cameron's leadership.
The Chancellor George Osborne today dismissed her as always opposing the Government.
Other critical MPs don't think it's got so bad that Mr Cameron's position is under threat.
And Dorries has got form, as she has branded the PM and Chancellor as "arrogant posh boys."