A perception that David Cameron does not like single parents is "electoral halitosis", his former spin doctor has warned.
Andy Coulson said the Prime Minsiter's "avidly" pro-marriage statements gave the impression he was "somehow anti single-parent".
He also called for Samantha Cameron to campaign harder to help the Tories win the next election.
His comments come from an article for GQ magazine where he claimed Boris Johnson wanted Cameron to "fail miserably" so he could ride to the Tories' rescue.
Coulson - who quit his job in January 2011 after being dragged into the phone hacking scandal - also cautions Cameron against dodging televised debates during the next election campaign - saying he would look "chicken".
And he said the chances of the Conservatives winning a majority in 2015 were "slim but still quite possible".
The former News of the World editor said more events alongside his wife would help the premier's image as a "family man".
"The time has now come for Sam to play a more public role and take some risks," he wrote.
"She only joined the 2010 campaign once it formally kicked off. She should now be persuaded that the 2015 campaign
is already under way and she's badly needed in the trenches.
"I wouldn't advise a dramatic change to the type of appearance she makes. I'd just like to see more of them."
Sam Cam Cameron needed to "show that she's not only supportive of her husband but is also fully committed to a longer term future in Number 10 herself".
"Sam might also take a more active part behind the scenes," Mr Coulson went on. "With the absence of so many original advisors, she is one of the few people able to see straight to the heart of the matter and offer a clear, sensible view.
"This will naturally steer clear of policy discussion but it should not stop her joining select small strategy meetings.
"There are few people in Number 10 with a better eye and she could play a key role in the winning back of female voters."
The ex-News of the World editor - who is due to stand trial later this year - said Foreign Secretary William Hague should be tasked with neutralising the threat from Nigel Farage's UK Independence Party (Ukip).
Former defence secretary and leading right-winger Liam Fox , who has been "under-employed" since resigning in 2011, should also be enlisted to help.
Coulson described a "surreal" conversation with Ken Clarke during the last general election campaign.
The frontbencher phoned to say that a reporter from the Daily Mirror dressed as a chicken had chased him to a
Coulson said: "The Mirror should hang on to that chicken suit if rumours that Number 10 are considering ditching live election TV debates are even slightly true."
He dismissed the 'myth' that the Tory leader lost all three events in 2010, and insisted he could benefit this time from talking about his acheivements in office.
Downing Street should "make clear now that the debates are very much on", he added.
Mr Coulson suggested Mrs Cameron would agree that her husband should mention single parents more often when emphasising the importance of family.
"The sneaking suspicion that in being avidly pro marriage he is somehow anti single parent lingers unfairly in the media and is electoral halitosis for the female vote," he wrote.