According to The Sun, Hutchings made the comments online after the inconclusive 2010 general election.
In an embarrassing revelation for Cameron, she is said to have slammed the prime minister for making “a pact with the devil”.
Hutchings added: "The Lib Dems have a reduction in seats and yet they might help govern Britain — INSANE."
The Tory candidate has already stoked controversy by suggesting that her son would need private education if he wanted to realise his dream of becoming a surgeon.
If Hutchings does win Chris Huhne's vacated seat on 28 February, it is unlikely Cameron will be gaining a loyal backbencher.
She is opposed to the coalition's gay marriage bill spearheaded by the prime minister and has said she would vote to leave the European Union if given the chance.
The increasingly acrimonious battle for the Lib Dem-Tory marginal reflects the importance each leader places on victory.
For Nick Clegg successfully holding the seat will show that his party is perhaps not headed for electoral oblivion.
For David Cameron, failure to win the southern constituency will prompt questions about how he can increase the Tory share of the vote at the next election.