Rep. Tom Allen (D-Maine) still has yet to close the double-digit gap between him and Sen. Susan Collins (R-Maine), according to new poll data from Research 2000 and sponsored by the liberal Web site DailyKos.com.

Collins led Allen in the poll, 57 percent to 38 percent, among 600 likely voters surveyed Sept. 8-10. The poll had a 4 percent margin of error.

The poll is the first publicly released survey since Allen and Collins have gone up on air with television advertisements. After more than a year of Allen trailing Collins by double digits in public polls, Democrats thought Allen would close the gap once his ads were on the airwaves.

The survey also showed Democratic presidential nominee Sen. Barack Obama (Ill.) leading Republican presidential nominee Sen. John McCain (Ariz.), 52 percent to 38 percent, in the Pinetree State