The renovation of Cal's Memorial Stadium is progressing as planned. The financing is not.

Fundraising efforts to pay for the stadium's $321 million renovation are "somewhat behind" ambitious goals, athletic director Sandy Barbour said Thursday.

The stadium is set to reopen with a Sept 1. game against Nevada.

Using an elaborate financing plan hooked to the sale of premium seats, Cal set a goal of raising $270 million by summer 2013.

To date, it has just $35 million in cash on hand.

The situation has created concern within a Cal community dealing with rising tuition and slashed budgets, and it was cast in dire tones Wednesday by The Wall Street Journal.

But John Wilton, Cal's vice chancellor for administration and finance, said that even in a worst-case scenario -- in which Cal sells just 70 percent of the premium seats before its June 2013 deadline -- the fund established to service the bonded debt would not run out of money until 2038.

"We have a long time to take action,'' he said, adding that university officials "will do everything we can'' to avoid using state money.

Even if Cal avoids the worst-case scenario, it will take a significant improvement in fundraising for the university to avoid a massive shortfall.

Stanford economics professor Roger Noll, an expert in stadium financing, noted that Cal also must service the debt on the new $153 million Simpson training center: "It's a long-term, serious financial problem" that, combined with the budget cuts to the UC system, constitute a "double whammy."

Noll consulted with Cal's faculty budget committee while the financing plan was being created. He believes the fundraising goals were "extremely ambitious," especially when compared to similar projects at Texas and Michigan -- huge state universities that have first-rate academic reputations but more football tradition than Cal.

"Cal's proposal was based on the expectation of raising three-to-five times the amount of the other schools," Noll said. "That seemed implausible."

Projecting the fundraising shortfall is extremely difficult because of the complicated nature of the financing plan.

It relies on numerous revenue streams, including a facility fee, philanthropy and increased rights revenue from Cal's share of the Pac-12 Conference's $3 billion deal with ESPN and Fox.

But the heart of the financing plan is the Endowment Seating Program, which allows fans to buy 50-year rights to approximately 3,000 premium seats. The payments can be financed over time, like a mortgage, and are placed into a fund that's used to service the debt.

According to Cal's latest financial report, which covers donations through March 31, the cash on hand equates to a long-term value of $145 million. That's slightly more than half the ultimate goal of $270 million.

"The situation is not as bad as the numbers ($35 million) because some of the people who paid the first installment will pay the second,'' Noll said.

But the difference between the Endowment Seating Program plan (ESP) and a mortgage -- and it's a monumental difference -- is that participants can drop out of the ESP at any time without penalty.

In other words, there's a chance the $35 million cash on hand won't ever become the $145 million in Cal's projections.

Central to the fundraising success is the football team's performance. The pressure's on coach Jeff Tedford, whose team is projected to finish in the middle of the Pac-12 North this fall. Cal is attempting to boost ticket sales and interest in the program by conducting its first spring football game in three years on Saturday.

"The team's success always impacts our ability to sell tickets," Barbour said.

For more on college sports, see Jon Wilner's College Hotline at blogs.mercurynews.com/collegesports. Contact him at jwilner@mercurynews.com or 408-920-5716.