Around the same time the Republican leader of the state Senate, Joseph Bruno, was investing his money and his campaign funds in Plug Power, a venture firm run by the fuel cell manufacturer’s chairman received tens of millions of dollars in state pension fund money through a program spearheaded by Mr. Bruno.

In August 2000, a little-known investment program administered by the state comptroller’s office agreed to invest $50 million in FA Technology Ventures, a fledgling venture firm spun off of First Albany Companies, an investment-banking boutique that specializes in municipal bond trades.

The funding from the state represented almost half of the money that Albany-based FA Technology Ventures had raised on its own in a market dominated by New York City firms.

The managing partner of FA Technology Ventures, George McNamee, is chairman of Plug Power, a startup fuel-cell manufacturer based in Latham, N.Y., that sold more than $100,000 of stock to Mr. Bruno and his re-election campaign committee in the same year. Mr. Bruno was one of perhaps a tiny handful of politicians in Albany who has invested campaign money in an individual stock.

Mr. McNamee was traveling yesterday and not available for comment.

Mr. McNamee is a major player in the capital district’s high-tech region who serves as a director of several members of FA’s investments portfolio, including Plug Power and Autotask, a privately held software company that last year received a $195,000 capital grant for new office space. The grant was sponsored by Mr. Bruno.

While no one is accusing Mr. Bruno of directing the comptroller’s office to make that investment, the timing of the stock buy and the flow of money to Mr. McNamee’s venture firm raises questions about the majority leader’s influence over the pension fund program, which was created to give upstate New York a boost in the venture capital market.

Around the same period in 2000, Mr. Bruno also incorporated his consulting firm, Capital Business Consultants, which has been under federal investigation since last year. Mr. Bruno has said he is a subject in an investigation that is focusing on his business relationships “going back five or six years.”

A spokesman for Mr. Bruno’s office and the comptroller’s office denied that Mr. Bruno played any role in the investment. “We have nothing to do with that because the comptroller did it,” a spokesman for the majority leader, John McArdle, said. “We had a great idea. It became law.”

In 2005, Mr. Bruno sold his personal and campaign committee shares of Plug Power — along with stock in a related company that was also controlled by Mr. McNamee — at a loss. Shares of Plug Power, which has relied on investments from New York government entities, hit a peak of $149.75 in 2000, plummeted to about $15 by the end of the year, and then gradually declined to a current value of less than $4.

The state venture capital program was a key part of Mr. Bruno’s legislative agenda in 1999. Officially called the New York Venture Capital Investment Program, it was part of the Senate’s Jobs 2000 for New York State Act, which Governor Pataki signed into law in November 1999.

The program authorized the state comptroller at the time was, H. Carl McCall, to carve out $250 million from the state pension fund for private equity fund general partners, who would then disperse it in small chunks to companies in New York, primarily technology companies. The investment risks were greater than ordinary pension fund investments, but potentially more lucrative.

Mr. Bruno stood with Mr. Mc-Call in announcing that FA Technology Ventures was the first firm the comptroller’s office had selected to receive a portion of the $250 million.

As of May 2006, the retirement fund has allocated a total of $425 million to 15 fund managers located in various areas of the state.

A report issued by the comptroller’s office last year said the investment program has “proven to be an important contributor to the state’s economy by making capital available to small businesses,” and said all of the 15 fund managers, including FA Technology Ventures, “are performing well and are establishing themselves.”