The Arts Partnership has delayed by one year the start of a $75 million building project at the Ordway Center in St. Paul. It was announced late last year that the project would break ground this spring, but officials said Thursday they have not raised sufficient funds to proceed.

"This is a very tricky time for fundraising," said Patricia Mitchell, the Ordway's CEO and president. "We're confident we're going to get there, but it has its own tempo."

Mitchell said that $55 million has been pledged (up from $51.5 million when the project was announced in December). Even though that would cover construction costs of $35 million, Mitchell said the Arts Partnership wants to secure the entire $75 million before embarking. An operating endowment fund is pegged at $32 million, and transitional costs of $8 million account for the rest of the project.

"We're committed to having the endowment piece before we do it," Mitchell said.

The partnership consists of the Ordway, the St. Paul Chamber Orchestra (SPCO), the Minnesota Opera and the Schubert Club. These groups agreed to expand the performing-arts center to create a primary home for the SPCO.

Fundraising has included $3 million from the city of St. Paul and $16 million in state bonding. An anonymous donor gave $5 million. Mitchell said the delay will not affect any of those pledges.

The new hall, to be built in a space now occupied by the 306-seat McKnight Theatre, would seat 1,100. The SPCO currently performs half of its concerts in the 1,900-seat main hall at the Ordway, and half in neighborhood venues. That ratio would not change, but by dedicating a separate space to the SPCO, the Ordway has greater flexibility in scheduling the larger auditorium. What would be lost is the theatrical program of the McKnight, which is used by local companies and some national producers.

HGA Architects of Minneapolis designed the new hall. With the delay, completion is now anticipated in 2015.