Lawmakers charged with the final signoff on a proposed senate office complex won't consider it before a public hearing next month, despite warnings that delays could drive up costs of the $272 million Minnesota State Capitol renovation.

The wait may indicate that pushback on the plan spans more than party lines. A March groundbreaking for the project now is on hold, although Capitol renovation continues with a blueprint contingent on a new Senate building.

"If that falls apart because the new building falls apart, I predict there will be tens of millions of dollars of cost overruns in the Capitol renovations because the key projects are so closely linked," Senate Majority Leader Tom Bakk, DFL-Cook, said Monday following a meeting of the Capitol Preservation Commission.

The Senate Rules Committee, chaired by Bakk, swiftly approved the project last month over protests from Republican members about the lack of public input.

The House Rules Committee, also led by DFLers, has been less eager. House Majority Leader Erin Murphy, who chairs the rules committee, said that before any vote, her committee will hold an informational hearing later this month that will look into alternatives, such as leasing space outside the Capitol to accommodate the Senate during renovations.

"Here's what I know," Murphy said. "There's a lot of bipartisan support for the restoration of the Capitol, which will result in functional upgrades and additional public space, leading to the question about Senate space. The Senate has proposed an office building and House members are concerned with that."

The $63 million building and adjoining $27 million parking facilities were approved in a tax bill at the close of the 2013 legislative session, requiring only a simple majority rather than the 60 percent required for bonding projects. The methodology drew ire from Republicans, also aggrieved over an opulent design and planned capacity for just 44 of 67 senators.

Wayne Waslaski, senior director for real estate and construction services for the Department of Administration, told the Senate Rules committee last month that recouping the cost of an outside lease would mean expending "multiple millions of dollars."

Senate offices are scheduled to be moved from the Capitol into the new building once it's completed in June 2015, followed by hearing rooms. Senate sessions also would take place there in 2016 while the chamber is renovated.

If plans for the new building are scrapped, Waslaski said, "There really isn't other space to do this around campus." Capitol renovations are set for completion in 2017.

Rep. Matt Dean, R-Dellwood, who sits on the rules committee, acknowledges the proposed building is critical to Capitol renovations, but "how these two are combined is a problem."

"The Capitol restoration has bipartisan support and has been developed over a long period of time," he said. "The Senate Office Building appeared on the tax bill and was passed without bipartisan support. I think the public is reacting to it because they don't really understand it. They don't understand the need for it and from what they have seen, it looks like the process was not carried forward in a respectful manner."

Bakk said the renovation of the Capitol is too important for what he called political gamesmanship.

"It's an election year; there's plenty for people to run on," he said. "We're making permanent revisions to this building that are only made possible by the new building. Or we can renovate [the Capitol] into a Senate office building, I guess, but that's not my preference."

Abby Simons • 651-925-5043