DENVER – A landmark expansion of background checks on firearm purchases was approved Friday by lawmakers in Colorado, a politically moderate state that was the site of last year’s mass shooting at a suburban Denver movie theater.

The bill previously passed the state Senate and now heads to Democratic Gov. John Hickenlooper, who is expected to sign it into law within two weeks.

Earlier this week, Colorado lawmakers approved a 15-round limit on ammunition magazines. It is also awaiting the expected approval of the governor.

The bill passed Friday expands cases when a $10 criminal background check would be required to legally transfer a gun. Republicans have opposed the bill, calling it an undue burden on law-abiding gun owners.

“We know for a fact that whatever law we pass criminals won’t care,” said Republican Rep. Jerry Sonnenberg.

The vice president praised passage of the bill.

“Congrats to Colorado House and Senate for passing universal background checks,” read a tweet sent by the office of Vice President Joe Biden from his official #VP account.

It was followed by another tweet referring to the theater shooting that read, “The families of Aurora deserved a vote and got one. Now U.S. Congress must act too.”

Congress is also considering a number of new firearm restrictions.

Colorado is the first state outside the East Coast to significantly ratchet back gun rights after the theater and school shootings. Colorado’s gun debate was being watched closely because it’s considered a swing state with both a gun-loving frontier past and an unfortunate history of mass shootings, including the 1999 Columbine High School attack.

“Are we going to stop all criminals from getting guns? No,” said Democratic Rep. Beth McCann, a sponsor of the background checks bill. “But are we are going to put a barrier there, make it more difficult for them? Yes.”

The move to expand background checks would be one of the most sweeping responses by Colorado to the shootings last year in Aurora and at the elementary school in Newtown, Conn.

In Colorado, expanded checks have been a top priority for Hickenlooper, who called for the proposal during his State of the State address in January.

Both chambers previously approved the expanded checks in slightly different forms. However, both had to agree on an identical bill before passing it to the governor, so a second round of voting was required.

From 4-H members learning gun safety but needing to borrow a shotgun, to neighbors on weeklong elk-hunting trips, Republicans argued the bill would ensnare harmless gun users.

Democrats insisted that existing exemptions in the bill would cover most scenarios the GOP imagined.

The bill’s sponsor, Senate Democratic Leader Morgan Carroll, told Republicans that Democrats had enough votes to pass the measure but extended debate to make small changes requested by Republicans.