The Colorado Senate on Tuesday narrowly advanced a bill to raise the overtime threshold for agricultural workers, defeating more than a dozen amendments from its leading opponent aimed at rewriting the measure.

As introduced, Senate Bill 121 would raise the threshold for overtime pay from its current 48 to 56 hours during production season to 60 hours.

The bill was amended by the Senate on Tuesday with 56 hours as the threshold.

SB 121 is sponsored by a bipartisan group that includes Senate Majority Leader Robert Rodriguez, D-Denver and Senate Minority Leader Cleave Simpson, R-Alamosa.

But Sen. Jessie Danielson, D-Wheat Ridge, who sponsored the 2021 legislation that led to the 48-hour threshold, mounted a lengthy attack on the bill, with a dozen amendments carried by other Democratic senators.

Danielson ran a competing bill that would have lowered the threshold to 40 hours, but the measure was rejected last week by the same Senate Business, Labor, and Technology Committee that advanced SB 121.

Danielson is the committee’s chair.

Simpson noted that lowering the threshold to 40 hours will force farmers to mechanize, eliminating workers. It would also reduce workers’ total pay when farmers cut off hours at 40 to eliminate overtime pay.

Two studies have shown that each farm worker loses thousands of dollars annually due to 40-hour workweek laws in agriculture.

Rodriguez argued that farmers can’t simply raise their prices to cover higher labor costs because market forces—not individual producers—set what they can charge.

At the end of the debate, Sen. Adrienne Benavidez, D‑Adams County, who planned to vote against the bill, said it was the first measure since she joined the Senate last month that received the level of debate it deserved.

Two amendments with recorded votes during the committee of the whole report could be an indication of how the final vote will look. The amendments, which sought to raise the bill’s threshold to 40 hours, failed on 11-23 and 12-22 votes.

The bill will move on to the Senate for a final vote, which could be as soon as Wednesday.