A sweeping measure aimed at cracking down on illegal immigration passed its first legislative hurdle Friday, after its sponsor, Sen. Bill Hickman, R-St. George, said he wanted to "get the clock ticking."

"It's very important we address this issue today," Hickman told the Senate Government Operations Committee. "I don't want to start looking like the federal Congress and say let's put it off for a year."

The committee agreed with Hickman in a 4-2 party-line vote after nearly two hours of testimony, in which lawmakers questioned what SB81 would mean in practice.

The bill is aimed at curbing undocumented immigrants from obtaining jobs or public benefits. According to a fiscal note released Friday, the measure would cost the state more than $1.8 million in fiscal 2009 and nearly $1.4 million in 2010.

Sen. Ross Romero, D-Salt Lake, unsuccessfully tried to send the bill to interim study, which would facilitate SB97, a separate measure sponsored by Sen. Scott Jenkins, R-Plain City, to create a task force aimed at researching the issue.

In voting against the bill, Sen. Scott McCoy, D-Salt Lake, said, "I think we're operating with a fraction of the information."

Friday's vote came after the bill was amended to remove a provision to repeal a 2002 law that allows undocumented students pay in-state tuition if they attend a Utah high school for three years and graduate. The amendment also removed a requirement that companies withhold state income taxes at the highest rate for independent contractors who don't provide proof of legal status.

Jenkins, who supported SB81, had unsuccessfully tried to amend the bill to delay its implementation until July 1, 2009. Currently, a few of the employment provisions will be delayed but most will become effective this year.

After the hearing, Jenkins said he'll again try to amend the measure on the Senate floor because he wants to "slow down a little bit" and wait on federal action. Hickman, who chairs the Rules Committee, said Jenkins' bill will likely be sent to committee on Monday.

Hickman said he'd support Jenkins' proposal as a way to provide guidance on any future actions and any clarifications that may be needed on his own measure.

"This may not solve all the problems," Hickman said. "This is a work in progress ... we may come back and make refinements."

Those opposed to the bill had hoped the committee would pass on Hickman's bill, in favor of Jenkins'.

"We have to inspire whoever is on our side to speak out as loudly as the other side allegedly is," said Dee Rowland, a spokeswoman for the Catholic Diocese of Salt Lake. "This bill has so many vague features it will affect all of us."