Obama, a U.S. senator from Illinois, moved from 63 percent to a level of support of 77 percent among conservative Democrats interviewed for a Gallup poll Monday through Wednesday of this week.
The support helped bump Obama to a 6-percentage-point lead in the poll over his likely main opponent Sen. John McCain, R-Ariz., Gallup reported Friday. Obama and McCain were tied at 45 percent in a Gallup poll last week.
In the most recent poll, Obama gained 3 percentage points among women and 3 percentage points among men. Unchanged was support for Obama from 92 percent of liberal Democrats and 79 percent of moderate Democrats.
This week's poll interviewed 1,411 registered Democrats, and those leaning toward voting Democratic, and had a margin of error of 3 percentage points.