Almost half of Britons do not even know who he is. And among those who do, Duncan Smith is badly trailing Labour Prime Minister Tony Blair and the minority Liberal Democrat leader in the popularity stakes, says the survey.
The news comes at an especially bad time, coinciding with the first day of his party’s conference, and is likely to increase pressure on the beleaguered Tory leader.
Despite a recent decline in support for Blair, a miserly 14% of those interviewed said they would choose Duncan Smith as prime minister.
About 35% preferred Blair and 22% Liberal Democrat leader Charles Kennedy, according to a poll by the Yougov agency for Sky News.
More than 80% of those polled were unsure of whether the Tory leader could run a form a competent government, while 57% said Duncan Smith was not the right man to lead the Conservatives.
Tory voters unimpressed
Even Conservative voters have little faith in their most senior representative. Some 44% of Conservative voters said they did not have confidence in him, while only 16% said the same of Blair.
Echoing these findings, an NOP poll showed 41% of the British electorate feel Kennedy's Liberal Democrats constitute the main opposition to the ruling Labour party.
A paltry 53% of those questioned between 26-29 September were able to name Duncan Smith as Conservative leader.
Still, in party political terms, the Tory Party has benefited from controversy surrounding Blair’s support for the US-led invasion of Iraq.
The Labour and the Conservative parties are now neck-and-neck with 33% support. The Liberal Democrats, if an election were held today, would win 28% of the vote.