When news of Eliot Spitzer’s prostitution scandal broke, the first take by the online columnist Mickey Kaus was that this was a setback for the teachers unions, because the lieutenant governor, David Paterson, is for private school vouchers.

It turns out that Governor Paterson is not for vouchers. But some of his other views on education could have teachers unions here on edge.

Mr. Paterson is linked to the United Federation of Teachers — his father, Basil Paterson, is a top lawyer for the union and a close ally of its president, Randi Weingarten — and he has sometimes stood with the union. Shortly after becoming lieutenant governor, he spent the first day of school standing by Ms. Weingarten’s side as she demanded mandatory caps on class size, a position the Bloomberg administration opposed.

But Mr. Paterson has also repeatedly taken positions that are at odds with the union. In 2003, as a Harlem state senator, he stood beside Mayor Bloomberg as the mayor announced a plan to house charter schools in public buildings. The schools are not guaranteed public space, although they are public schools financed with taxpayer dollars. Against the union, he has also supported charter school expansion; education tax credits for private school parents, and a proposal to have a private for-profit company, Edison Schools, take over some city public schools.

With the state facing several high-stakes education battles in the immediate future — there is a budget to be written; a decision on the city’s mayoral control policy to be made, and an escalating conflict over teacher tenure — the independent streak makes Mr. Paterson a page upon which people who call themselves “reformers” are projecting grand hopes. “A rock star,” is how the lobbyist Michael Tobman, a supporter of education tax credits, described Mr. Paterson.

An “education gov” who will courageously tackle once-taboo subjects, Thomas Carroll, president of the Foundation for Education Reform, declared in The New York Post the day Mr. Paterson was sworn in.

The co-chair of the think tank Education Sector, Andrew Rotherham, writing on his widely read blog, Eduwonk, applauded Mr. Paterson as “even more hardcore about school reform” than Governor Spitzer.

In an interview this week, Ms. Weingarten also showered Mr. Paterson with praise, calling him “a transformative elected official.” She dismissed predictions by charter school supporters such as Messrs. Carroll and Rotherham as not “artful.” “It just seemed like they were in some ways trying to put words in his mouth,” she said.

“He is his own thinker, he’s someone who understands adversity, he’s someone who has constantly been underestimated, and I think he’s going to make a terrific governor,” she said.

Though Ms. Weingarten said she was taken aback, the outpouring of support from so-called “reformers” is nothing new for the governor.

Mr. Paterson is a friend of several prominent voucher supporters, including the mayor of Newark, Cory Booker, and the Milwaukee activist Howard Fuller. In 2006, the No. 1 contributor to his campaign for lieutenant governor was the lobbying group Democrats for Education Reform, which gave Mr. Paterson $49,000, or 3.56% of his total contributions, data collected by the National Institute on Money in State Politics show.

The hedge fund manager who has founded a network of Harlem charter schools, Joel Greenblatt, also hit the list of Mr. Paterson’s top contributors, donating $16,200.

Sources said activists are won over by the passionate and honest way Mr. Paterson speaks about education. To defend his support for giving students options, Mr. Paterson invokes the experience of his own children, one source close to him said.

His son attends a public middle school in the city — but, though the family lives in Harlem, the son travels outside his neighborhood for school. “There was no public school in Harlem he could find,” the source said. “It’s a personal issue for him.”

The power of Mr. Paterson’s words on the subject is illustrated by a campaign contribution that has raised the most eyebrows, a $100 donation from the voucher proponent Clint Bolick in 2006 that is behind the speculation by Mr. Kaus and others that Mr. Paterson is a voucher supporter.

The donation was one of 12 simultaneous gifts voucher and school choice supporters delivered to Mr. Paterson, all on January 10, 2006. The donations totaled $14,350, disclosure reports show.

They came a few months after Mr. Paterson flew to Colorado to speak at an annual gathering of voucher and charter school supporters. In his speech, Mr. Paterson stressed the importance of choice but did not use the word vouchers, two people who attended said.

“He left a favorable impression on a number of people,” one donor, a Milwaukee education consultant named George Mitchell, said. “You get a fairly good BS antenna after a while, in terms of listening to folks, and he really seemed like he was talking real straight to the group.”