DFL U.S. Senate candidate Al Franken got a welcome boost on Wednesday with an endorsement from one of the more revered figures in the Democratic Party -- former Vice President Al Gore.

Gore, who has become a crusading environmentalist since leaving elective office, sent an e-mail to DFL delegates on Wednesday afternoon that warmly praised Franken, calling him "exactly the breath of fresh air our government needs."

Calling Franken one of the party's "hardest working activists," Gore saluted what he said were Franken's "sharp wit and strong convictions." In a nod to the unconventionality of Franken's candidacy, Gore said the entertainer/author "definitely won't be your typical Washington politician ... . Al will be passionate and principled and wonky and honest and, yes, funny -- sometimes all at once."

Franken has had several stumbles lately, most recently with the resurrection of an explicit satirical sex fantasy he wrote for Playboy in 2000.

Several high-level DFLers have criticized the piece and on Wednesday, Rep. Jim Oberstar offered his most pointed remarks yet on the topic, calling on Franken to "disown" the piece.

In an interview with the Brainerd Dispatch, Oberstar said that he expected Franken to win endorsement at this weekend's state convention and remained a supporter, but said he was disappointed at the Playboy piece, which he called "so amateurish and so silly."

On Wednesday, Franken campaign spokesman Andy Barr reiterated what has become the campaign's standard response to criticisms of his off-color writings and comic musings, saying that "Al has made clear that he understands the difference between the job he had as a writer and comedian and the job he's asking Minnesotans to give him as their senator." Barr said that it "is certainly exciting to know that Chairman Oberstar foresees victory for us. [Franken is] looking forward to having his support."

Meanwhile, Franken's DFL rival, Jack Nelson-Pallmeyer, announced an endorsement of his own on Wednesday -- that of the man who piloted U.S. Sen. Amy Klobuchar to victory in 2006, former campaign manager Ben Goldfarb.

Nelson-Pallmeyer, Goldfarb said, would be a "stark contrast" to U.S. Sen. Norm Coleman, R-Minn., and is best suited to reclaiming the seat once held by the late Sen. Paul Wellstone.

In the e-mail, Goldfarb said that while he would back Franken if he became the nominee, "I strongly believe that Jack's life story, courage, and authenticity" would give him the advantage.

Franken and Nelson-Pallmeyer will by vying for party endorsement this Saturday at the party's state convention. Both candidates have promised to abide by the endorsement and avoid a primary.

Patricia Lopez • 651-222-1288