DENVER — The first of four Democratic gun proposals to be heard Friday, a ban on high-capacity magazines, cleared the statehouse on an initial voice vote around 3 p.m. after a six-hour debate.

“Over the course of the last four or five years, we’ve had 34 mass shootings using high capacity magazines,” said Rep. Rhonda Fields, D-Aurora, whose district includes the Century 16 theater where 12 people were killed in a mass shooting last July.

“That is the common thread we see in these massacres. They’re using these high-capacity magazines so they can unload as many bullets as they can to kill as many people as they can, in our schools, in our theaters and in our churches.”

A parade of Republicans took to the well Friday to speak at length in opposition to every aspect the bill; but the Democratic majority, with at least three members breaking ranks and voting against House Bill 1224, passed the measure on second reading over those sustained objections.

“If you vote for this bill, you are gambling on the safety of Coloradans,” said Minority Leader Mark Waller, R-Colorado Springs. “There is no evidence that banning these magazines will have any positive impact on public safety and you are taking them away from responsible, law-abiding citizens.”

Republicans also focused attention on Boulder-based Magpul Industries, the $400 million magazine manufacturer now threatening to leave Colorado if this ban becomes law; and, five hours into the debate, the House GOP informed reporters that a Magpul supplier, Alfred Manufacturing, may also have to move its Denver plant, and 150 jobs there, to another state.

Democrats amended the bill to allow Magpul to continue to manufacture high-capacity magazines in Colorado for sale in other states, but the company remained opposed to the ban.

Republicans argued that the amendment, which would enable the continued use of magazines of more than 15 clips elsewhere, illustrated hypocrisy.

“Now we know what this bill is really about,” said Rep. Jerry Sonnenberg, R-Sterling. “It’s all about the money! Is that what this bill’s about? That we don’t care about other people across the country?”

Democrats said they’re simply striving to find a balance that protects affected businesses while improving public safety.

“This represents us listening to a constituency base,” said Rep. Joe Salazar, D-Thornton.

Rep. Chris Holbert, R-Parker, referred to the amendment as “the oops amendment”, arguing that Democrats forgot about the impact on businesses when drafting the bill.

The strident opposition to House Bill 1224, one of the two measures the House GOP entered the day with hope of defeating, presaged a long floor fight over the four Democratic gun control measures that Is expected to last late into the night and possibly Saturday morning.

Republicans began the day hoping they can find five Democrats to vote against the bill and help kill it; at least four Democrats have expressed reservations but House Speaker Mark Ferrandino is confident that the high-capacity magazine ban will pass the House at the end of this long debate.

One moderate Democrat who Republicans needed to vote against the bill, Rep. Mike McLachlan of Durango, had already voted for the ban during the House Judiciary Committee hearing on Tuesday.

On Friday, he strode to the well to inform his colleagues he’d be doing so again.

“I rise in support of this bill,” said McLachlan, a Vietnam Vet who narrowly won a GOP-leaning district last November, sounding the unofficial death knell for the GOP’s attempted filibuster.

“No constitutional right, even the Second Amendment, is absolute.”

Following the voice vote on the high-capacity ammunition ban, lawmakers immediately began debating House Bill 1226, which mandates background checks on all gun purchases in the state that is also sponsored by Fields.

The other measures before the House Friday, or perhaps early Saturday morning, include legislation to force gun buyers to pay for those background checks and a ban on concealed weapons on college campuses.