DENVER -- The Senate approved a measure that would make it easier for unions to set up in Colorado, causing the biggest rift between Democrats and Republicans since Gov. Bill Ritter took office a month ago.

House Bill 1072 was sent to Ritter to sign after it was approved on Monday.

Republican leaders will deliver a letter to Ritter after Monday's session urging him to veto the bill.

The bill would take away one of two worker elections needed to create an all-union workplace. All-union shop employees are required to pay union fees regardless of whether or not they join.

Under the current system, the initial vote requires a majority to decide to form a union and the second requires a 75 percent majority to form an all-union shop.

"Well, I'd like to know which politicians would like to get elected by 75 percent. That is un-American. It is majority rule in this country and so majority rule said govern," said Ernest Duran Jr., U.F.C.W. president.

Ritter has not been clear as to whether or not he will sign the bill, but has said that Republican businesses and lawmakers are overreacting to the measure.

"This is not a big deal. This is not the end of economic development in Colorado," he said on KOA radio in Denver.

Last week an eight-hour filibuster was staged by Republicans in an effort to stop the bill because they feel it would keep businesses from moving into Colorado and help Democratic-friendly unions raise money.

Republicans also said that the Democrats did not make it known to voters that the bill was on the agenda, and claimed Ritter put the bill on a fast track in an effort to pay back unions for their help in the recent election.

Ritter denied GOP charges.

"There was nothing about it that fast-tracked it. I think before it gets to my desk we'll have one other bill, perhaps two other bills that I will see that were not fast-tracked," Ritter said.

A spokesperson for Ritter said that while he was running for office he said he would be inclined to sign a bill like this one.