O’Malley lags far behind former secretary of state Hillary Rodham Clinton, who gets the support of 43 percent, followed by Vice President Biden -- who is mulling a run -- with 26 percent and Sen. Bernie Sanders (I-Vt.) with 20 percent.
Former Virginia senator Jim Webb is the choice of 1 percent, while former Rhode Island senator and governor Lincoln Chafee attracts less than 1 percent.
Clinton, Sanders, O'Malley, Webb and Chafee are set to appear together on stage here Tuesday night in a debate hosted by CNN that O’Malley has said should serve to significantly broaden his national exposure. His numbers among those in Maryland, who know him best, have not really budged since he began running.
The relative success in Maryland of Sanders -- whom O’Malley has called as a “protest candidate” -- may be especially galling for the state’s former governor, whose eight-year tenure ended in January.
Sanders was at just 3 percent support one year ago in Maryland, matching O'Malley's level. Since then, Clinton's dominant position has fallen 20 points, from 63 percent to 43 percent. Sanders has gained 17 points while O'Malley hasn't moved.
O’Malley has offered himself as a progressive alternative to Clinton, but Sanders, a self-described democratic socialist, has courted the liberal wing of the party far more successfully.
Sanders gets 29 percent support from self-identified liberals in the Post-U.Md. poll while O'Malley gets 6 percent.
O'Malley is unable to crack double digits among any Democratic voting group.
Biden, who is in second place in Maryland, has yet to announce whether he's running.
Maryland is scheduled to hold its presidential primary on April 26, well into the calendar for the Democratic nomination. O’Malley formally kicked off his campaign in late May in Baltimore, where he served two terms as mayor. But none of the presidential candidates have spent much time campaigning in Maryland since then.
The Post-Maryland poll was conducted Oct. 8-11 among a random sample of 1,006 adults residents of Maryland, including landline and cellphone respondents. Results among the sample of 490 Democrats and Democratic-leaning independent voters have a margin of sampling error of plus or minus five percentage points.