Rep. Tom Allen (D-Maine) announced Tuesday that he will challenge Sen. Susan CollinsSusan Margaret CollinsPressure rising on GOP after Trump–DOJ fight’s latest turn Trump's plan to claw back spending hits wall in Congress Dem rep to launch discharge petition to force net neutrality vote in House MORE, who is considered one of the most vulnerable Republicans, in 2008.

"Maine and America face unprecedented challenges," Allen said in this video announcing his run. "For the last six years, the Bush Administration, supported by a Republican Congress, has failed the American people."