A routine committee vote on an ambassadorship took an unexpected turn Tuesday when Sen. Chuck Hagel (R-Neb.) raised a surprise objection to President Bush’s nomination of a major Republican donor and Bush fundraiser.

In joining Democrats opposing the nomination of Ameriquest chief Roland Arnall as ambassador to the Netherlands, Hagel cited concerns about ongoing state investigations into the mortgage lending giant.

Hagel’s switch tied the Foreign Relations Committee vote, 9-9. But Chairman Dick Lugar (R-Ind.) tossed out nine proxy votes from Senators not in attendance. Counting only the votes of those committee members who were physically present at the hearing, the nomination was approved, 8-2.

Now, Democrats say they will challenge Lugar’s move on the Senate floor, seeking a ruling from the chair.

“We’re trying to figure this out ourselves,” said Jesse Jacobs, spokesman for ranking member Sen. Paul Sarbanes (D-Md.).

A Democratic aide called Lugar’s interpretation of committee rules “erroneous and unfortunate.”

“If that’s what the rules said, what in the world is the purpose of having proxy votes?” the aide said.

Lugar spokesman Andy Fisher said, “Committee rule 4(c) on reporting says: ‘The vote of the Committee to report a measure or matter shall require the concurrence of a majority of those members who are physically present at the time the vote is taken.’”

If Lugar’s use of the rules is overruled on the floor, the nomination would likely go back to committee, the Democratic aide said.

Should the challenge fail, it is unclear whether a Democrat would place a hold on Arnall’s nomination. “We’ll cross that bridge when we come to it,” Sarbanes spokesman Jacobs said.

“The Senator’s general sense of this is that people we send abroad to represent the country should be clear of questions about their conduct or business interests,” said Hagel spokesman Mike Buttry.

Sarbanes, who also serves as ranking member on the Senate Banking Committee, was the first to raise objections about Arnall’s nomination, pointing to an ongoing investigation by 30 states into Ameriquest’s lending practices.

The company set aside $325 million this summer to pay out in settlements with the states, but an agreement hasn’t been reached yet.

Arnall and his wife, Dawn, have been prolific political givers.

Until President Bush’s election, they largely backed Democrats, contributing $360,000 to the Democratic National Committee in the 2000 cycle, and $1,000 each to Sens. John Kerry (D-Mass.) and Hillary Rodham Clinton (D-N.Y.).

After Bush first won the White House, Arnall found a number of channels to direct his cash the president’s way. He gave $1.8 million to first lady Laura Bush’s library foundation, personally contributed $2,000 to Bush-Cheney ’04 Inc. and served as a “ranger” for the campaign, rounding up at least $200,000 for the president’s re-election effort.

Ameriquest last year signed a 30-year deal, reportedly worth $75 million, to name the Texas Rangers’ stadium, for which Bush helped secure funding when he owned the team in the early 1990s.