Republican lawmakers in Colorado argue that a recently approved bill which recognizes gay and lesbian couples with civil unions will face legal challenges.

House lawmakers approved the measure on Tuesday, nearly one month after it cleared the Senate. Democratic Governor John Hickenlooper has said he'll sign the bill into law. It is expected to take effect in May.

Representative Lori Saine, a Republican from Dacono, is quoted by The Denver Post as saying that the bill will get a second debate in a court of law.

“We won't get to debate this again here, but we will debate this in a court of law,” Saine said.

Republicans attempted to advance several amendments to the bill as it was debated on the House floor, pressing for additional exemptions based on religious beliefs, including returning exemptions for child placement agencies omitted from last year's bill. Democrats managed to derail all attempts to amend the bill during a 4-hour debate which appeared to test House Speaker Mark Ferrandino's patience.

“I don't ask you to put your relationships up to a vote of the people,” Ferrandino, the bill's openly gay champion in the House, lashed out at Republicans attempting to tack on a provision to the bill calling for a public referendum on the issue.

Two Republicans, Cheri Gerou of Evergreen and Carole Murray of Castle Rock, spoke in favor of the measure.

(Related: Denver Post defends running photo of gay lawmaker kissing partner.)