Some 26 percent of party sympathisers oppose Sahlin, who is the sole candidate to take over from former prime minister Göran Persson, who led the party to defeat in September’s general election.
Sahlin is opposed by one in three male members of the LO union movement, which is affiliated with the Social Democrats.
Support for Sahlin is strongest in western Sweden, where 63 percent think she is the best person for the job. Sahlin is weakest in north-central Sweden, where only 38 percent want her to be selected.
The former minister is most popular among women, with 57 percent wanting her to get the job, while her support among men is 48 percent.
The group among whom support is strongest is Social Democrat-voting retired men, 73 percent of whom support her. Some 65 percent of women in 49-year-old Sahlin’s own age group want her to be leader.
Party members will get the chance to vote on Sahlin’s bid for the leadership at a congress in March. If elected, Sahlin will become the first-ever female leader of the Social Democrats.