The death of a prominent Democratic political adviser whose body was found in the water under the Golden Gate Bridge was being investigated as a suicide, authorities confirmed Thursday.

Duane Garrett’s body was found Wednesday afternoon near the bridge’s north tower, police said.

Garrett, 48, was a close friend and adviser to Vice President Al Gore, campaign cochairman for Sen. Dianne Feinstein, D-Calif., and a frequent fundraiser for Democratic and environmental causes.

The vice president called him “a man of many talents.”

“He was a renowned art collector, an avid sports fisherman, a dedicated environmentalist, a talented lawyer and a formidable political strategist,” Gore said.

Feinstein spoke emotionally of Garrett in a telephone interview from her Washington office.

“Duane was the kind of guy who let everybody see his heart. He was the last person you would dream of doing that,” she said of the suicide report.

Garrett was national co-chairman of Walter Mondale’s 1984 campaign for president.