The latest ITV News/ComRes poll suggests the London mayor Boris Johnson may not be as popular across the country as he appears to be at the Tory conference.
When asked who would be most likely to lead the Conservatives to victory in the next election, 27% said David Cameron and only 18% said Boris Johnson.
Only 34% think the Tories are more electable with Mr Johnson as their leader.
Boris has pledged his loyalty to the Prime Minister, telling the Conservative Party conference David Cameron will win the 2015 election.
London Mayor Boris Johnson will deliver a keynote speech at the Tory party conference, amid speculation about his leadership ambitions.