CHICAGO – An alumnus of the University of Illinois announced a $100 million gift to the Urbana-Champaign campus Friday, marking the largest single donation in the university’s history.

U of I, which is in the middle of a massive capital campaign, also announced two other donations Friday totaling $27 million. The university is the second in Illinois this week to announce a $100 million gift, the record amount for the largest single donation given to a university in the state.

“It’s the most exciting thing to happen at this university in terms of philanthropy,” said Urbana-Champaign Chancellor Richard Herman. “It’s a gift of passion, one that will mean transformation for us.”

U of I announced the gift just days after the University of Chicago announced a $100 million anonymous donation to be used for scholarships for lower-income students.

The U of I gift donated by alum Thomas M. Siebel, founder and former chairman of Siebel Systems Inc., is an estate provision _ meaning the university will receive the money after Siebel’s death.

But Herman said Siebel “has a sense of urgency about helping us attain excellence” and is open to the possibility of providing money sooner. Herman said a task force of faculty members will brainstorm ideas for Siebel to consider funding “ahead of time.”

It was not immediately known what the donation would fund.

Herman said he envisions professorships, research grants and new buildings incorporating ideas of energy and sustainability, topics that interest Siebel, who already has given millions to the university.

In 1999, Siebel, who graduated in 1975 and holds two masters degrees from the university, donated $32 million toward the construction of a new computer science building completed in 2004.

“He’s a man who has over many years engaged in helping us,” Herman said.

The university’s largest gift previously had been $40 million, given in 1985 by alum Arnold Beckman, founder and chairman of Beckman Instruments Inc., to create a science and technology institute.

The other gifts announced by university officials Friday include $22 million from James Grant, an alumnus of the university’s medical school, and his wife, Marion. The money will go to the College of Medicine in Chicago, according to Jim Gobberdiel, a spokesman for the University of Illinois Foundation.

Former faculty member Josef Lakonishok and his wife, Margot, also announced a $5 million donation to the College of Business on the Urbana-Champaign campus, Herman said.

U of I is in the middle of an eight-and-a-half year campaign to raise $2.25 billion, the biggest capital campaign in the school’s history and currently one of the largest in the country.

The school raised $990 million through the first four years, the so-called “quiet phase” of the campaign. The more public part of the campaign – which will include pleas for money from Illinois’ 563,000 living graduates – began Friday with a dinner at Navy Pier in Chicago and will end in 2011.

The university hopes to raise $1.5 billion for the Champaign-Urbana campus, its largest with 41,000-students. The goal for the 24,000-student Chicago campus is $650 million, and the 3,300-student Springfield campus is aiming for $28 million. The remaining $72 million would go to the University of Illinois Foundation and university administration.