They weren't helping the people in the Gulf Coast.
They were helping Alaska Senator Ted Stevens shoehorn his (in)famous "Bridge to Nowhere" through the Senate.
These two extremely liberal senators were aiding and abbetting the pillaging of funds meant to help Gulf Coast victims of Katrina in order to send them 3000 miles away for a stupid bridge. They were too afraid to stand up to Stevens.
Meanwhile, also in Alaska, another powerful government figure (In fact, the governor, Frank Murkowski, a friend and ally of Senator Stevens) was throwing his influence around, only to be thwarted by a local housewife. Her name? Sarah Palin. Read more (From The American Spectator, via Neil at 4Simpsons):
Senator John McCain, a longtime opponent of Stevens and the Bridge to Nowhere, is not in the Senate the day Coburn brings up his amendment, but is well on record as opposing the Alaska bridge. His relationship with Stevens over the issue of earmarks has been explosive. Senators Obama and Biden vote for this Stevens earmark — against giving the Bridge to Nowhere money to the Katrina victims who need their bridge rebuilt.[...]
Angered by what she calls the “lack of ethics” of a fellow Commission member, Palin resigns and files formal complaints against the GOP chair and Alaska’s GOP Attorney General. Both men are forced to resign, the party chairman paying a record $12,000 fine. Furious at the atmosphere of corruption, Palin turns her sights on the powerful Governor Murkowski, challenging him in a primary. She wins, and goes on to beat another Alaska insider, a Democratic former governor, to capture the governorship.