DENVER — When Tuesday began, House Republicans had a difficult choice: to allow Democrats to be the heroes for passing legislation recognizing same-sex civil unions or to play the villains themselves for killing it.

After a brief flash of drama on the House floor, Republicans decided to play the villains, calling an immediate recess as soon as Democrats attempted to bring the civil unions measure up for debate, and never going back on the floor, letting the civil unions measure die along with more than three dozen other bills.

Put simply, Speaker Frank McNulty chose the nuclear option.

“They have brought dishonor and ill repute on this House,” said Sen. Pat Steadman, who sponsored the civil unions measure, of House Republicans. “They ought to be ashamed.”

Even though a majority of state lawmakers approve of the bill, as does an even wider majority of Coloradans, House GOP leadership refused to allow the bill to come up for a vote before the full House.

“We’re at an impasse that’s not going to be resolved tonight,” McNulty, R-Highlands Ranch, told the media around 11 p.m. Tuesday night, after lawmakers had been lingering in the chamber for more than three hours as Republican leadership ran out the clock.

Boos rained down on McNulty as he left the House floor, as supporters of Senate Bill 2 chanted “shame on you” from the House gallery above.

“The House Republicans don’t want to let civil unions come up for a vote, that’s the impasse,” said Rep. Mark Ferrandino, the bill’s sponsor.

Gov. John Hickenlooper came back to the Capitol Tuesday night, attempting to broker a deal to get lawmakers back on the floor.

After sharing a whiskey with McNulty on the House lawn, Hickenlooper and staff spent 15 minutes with Ferrandino in his office.

But no deal could be reached.

As a result, 37 bills — sponsored by Democrats and Republicans alike — will die on the House calendar, failing to pass second reading in time to be given final passage on the session’s last day Wednesday.

Among them: a GOP-sponsored measure to create DUIs for driving while stoned, a $20 million dollar bill to fund water projects across the state, an autism study and a county clerk’s bill on elections.

House Republicans showed signs of obstruction early on Tuesday, as members of the House Appropriations Committee stalled for hours before hearing Senate Bill 2, which was amended twice before clearing the committee.

An hour later, Democrats were joined by two Republicans, Reps. B.J. Nickel and Don Beezley in blocking the House GOP from beginning debate on a slate of bills before they’d introduced the civil unions bill.

But once that bill was read across the desk, House Republicans went into recess immediately as soon as Democrats attempted a motion to bring that measure to the floor.

Had Democrats been recognized, their motion would have passed with both Nikkel and Beezley voting in favor of opening debate on the civil union bill.

Instead, the recess lasted the rest of the night.

Even some Republicans who opposed civil unions wanted the measure brought up for a vote so votes on other bills could proceed. For one, Rep. Tom Massey, R-Poncha Springs, made a case to McNulty to break the stalemate and end the recess, to no avail.

While McNulty and GOP House leadership continued to blame Senate Democrats for not passing S.B. 2 sooner, they still had plenty of time to pass the measure through the House and instead spent hours Tuesday night filibustering, eating up time by sending members to the well to drone on about another bill regarding trans fats in schools.

“House leadership decided today that it was more important to play politics than do the people’s business,” said Brad Clark, the executive director of zone Colorado, a statewide LGBT advocacy group.

“Although a clear majority of Colorado voters support civil unions—and a clear majority of our Representatives agree with them—House leadership killed the bill, proving just how out-of-touch they are with everyday Coloradans.”

Come November, voters will decide which party to blame for what most Capitol observers consider to be a meltdown of epic proportions.

“Instead of protecting all Colorado families, House leadership pandered to the far-right fringe of their party,” Clark continued. “We will now take our fight to the election, and come November, we will win a pro-equality majority that will vote to protect all loving couples.”

Mario Nicolais, a GOP attorney and spokesman for the group Coloradans for Freedom, conservatives who support civil unions, agreed with Clark.

“Civil unions will pass,” Nicolais said. “And so will the Republican House majority.”