As the University enters the fourth year of the Yale Tomorrow fundraising campaign, it has raised $1.73 billion toward its $3 billion goal, beating expectations. But some involved with the campaign said the pace of donations could slow over the next year.

Although the University is already more than halfway to its goal, many of the wealthiest alumni and other potential large-scale donors have already made their commitments to the campaign, campaign leaders said. That fact, combined with an economy that could be in the early stages of a recession, may translate to fewer gifts during the next year.

Generally, the middle years of fundraising campaigns are the slowest because the largest gifts are solicited during the first years, and the approaching completion of a campaign reinvigorates donors’ excitement, said Len Baker ’64, a member of the Yale Corporation and co-chair of Yale Tomorrow. Although the third year of this campaign was surprisingly strong, the momentum may not keep up, he said.

“I think that if it dropped off a little bit, we wouldn’t be disappointed,” Baker said. “That’s what you would expect.”

But for now, Baker said, there are many gift proposals on the table. This phase of the campaign has also been useful in identifying younger alumni who have not made large gifts to Yale before but are able to do so now, he said.

Depending on the progress of the campaign over the next year or two, the $3 billion goal could be increased to accommodate projects on the new “Yale West” campus in Orange, which was purchased from Bayer at the beginning of the summer. It may also be raised to fund two new residential colleges if the project is approved by the Corporation in the spring, University President Richard Levin said. How much the goal will go up will depend on the progress of the campaign, he said.

“We will have to see how this year goes,” Levin said. “Right now we are way ahead of the necessary pace. But it could slow.”

Any additional money raised for expanding Yale College would fund the expansion of facilities, while added tuition revenue from additional students would cover increased operating costs, Levin said. The construction of new colleges would necessitate several hundred million dollars worth of additional fundraising, Levin said.

This year, officials in the Office of Development and the five Yale College alumni who serve as co-chairs of the campaign will host regional campaign kickoffs in cities across the country. The first will be held in Boston later this month.

Although the campaign has been ongoing for three years, this past year was the first it has been public. During the first two years — dubbed the “silent phase” by administrators — it secured some of the largest gifts, including five gifts between $50 and $100 million. The campaign is comprehensive and encompasses everything from athletics to the internationalization of the University. The past year has seen gifts to fund a new campus for the School of Management, expand the education program for the art gallery and support the China Law Center at the Law School.

“We made good progress on all fronts,” Vice President for Development Inge Reichenbach said in an e-mail.