Gov. Rendell said yesterday that he would be willing to back indicted State Sen. Vincent J. Fumo's reelection bid in a four-way Democratic primary.

All the senator has to do is ask.

"He hasn't asked, and I haven't done a formal endorsement, but all things being equal, I probably would," Rendell said. "We would be lost in Harrisburg without him because of his skill. He has done great things, and we are lucky to have him."

Already, Fumo's campaign has aired TV ads that feature the governor's past quotes about the senator's tenure in Harrisburg.

One notes that Rendell, who is immensely popular in the city, has praised Fumo as "indispensable" in the fight for new gun laws. In another, he is quoted as calling Fumo "a tenacious fighter for Philadelphia."

Yesterday, the governor said he was aware that his words were being used by Fumo, and that he had approved of it, but that he still hasn't formally endorsed anyone in the April 22 first senatorial district primary - one of the highest profile races in the state.

In an interview with The Inquirer, Rendell singled out one of Fumo's challengers, electricians union leader John Dougherty, a steadfast political supporter of his. "I think the world of John Dougherty and his energy," he said, "but I always believe that if an incumbent has done his job and served the district well . . . he should be reelected."

Rendell then proceeded to again sing Fumo's praises, calling him "smart" and saying he "continues to be a strong, positive force" - despite facing 139 federal criminal counts.

"I still believe that people are still innocent until proven guilty," Rendell said.

The bottom line, Rendell added: "We would miss him in the legislature if he is not there."

Told of Rendell's strong words for Fumo, Dougherty said he regarded Rendell as "a great mayor, a great governor, and a very smart politician. He is in the middle of the budget process, so he had his smart-politician hat on, and understands Senator Fumo is still part of the budget process."

Ken Snyder, Fumo's media consultant, said last night, "It's always been our understanding that the governor would endorse Senator Fumo. It's just that that conversation hasn't happened yet. It will eventually."

Fumo's trial on fraud, conspiracy, and obstruction of justice is scheduled to begin in the fall. Prosecutors allege the powerful senator used his state staff and funds from a neighborhood charity to support an opulent lifestyle and then orchestrating a cover-up after the FBI started asking questions.

Political activist Anne Dicker and attorney Lawrence Farnese Jr. are also seeking the party's nomination.

The winner will face Republican Jack Morley in the fall. Former City Councilman and Controller Joseph Vignola, who plans to run as an independent candidate, also launched his campaign this week.

Contact staff writer Mario F. Cattabiani at 717-787-5990 or mcattabiani@phillynews.com.