Connecticut Senate Minority Leader John McKinney, R-Fairfield, who represents Newtown, Conn., left, is embraced by state Sen. Toni Boucher after the passage of a gun-control bill in the Senate chamber at the Capitol in Hartford, Conn., Wednesday. The bill passed the Senate and goes onto the state House for approval. Hundreds of gun rights advocates are gathering at the statehouse in Hartford ahead of a vote in the General Assembly on proposed gun-control legislation.

From Colorado to Connecticut, a handful of very different states have advanced new gun control laws over opposition that has made such legislation a struggle nationally and a non-starter in most legislatures.

How did they do it?

Culture and attitudes regarding guns vary widely from state to state and within their borders, but the limited victories by gun control advocates in the three months since the Newtown school massacre show three factors at work: governors willing to spend significant political capital on the issue; Democratic legislative strength; and heightened public concern raised by proximity to mass shootings.

All three helped drive new gun control measures in New York, Colorado and in Connecticut, where Gov. Dannel P. Malloy pushed for an agreement between majority Democratic lawmakers and Republican counterparts on a series of new laws that were headed for a vote Wednesday. In Maryland, which also has a Democratic governor and legislature, a gun control bill was proceeding through the House of Delegates.

"What makes the difference ... is the willingness of the legislators and the governors to take the lead and also, you know, the experience of gun violence in that state, whether it be through a mass shooting or the day-to-day shootings," said Lindsay Nichols, staff attorney for the Law Center to Prevent Gun Violence, a gun-control advocacy group based in San Francisco.

But in Illinois, where Chicago gang shootings have driven demands for a response, a standoff between legislators representing rural and urban voters with very different views - and the uncertainty raised by a court ruling on the state's concealed carry law - show that concerns about such backyard gun violence alone is not enough.

"More so than any other issue I can think of, this is an issue that is based on regional culture," said Charles Wheeler III, director of the Public Affairs Reporting Program at the University of Illinois-Springfield. "For the typical person who lives in downstate Illinois, the more rural areas, when you think of firearms you think of deer hunting, duck hunting, shooting squirrels. In the Chicago area ... when people think of firearms they think of the kind of horrific cases in the news of late, where a gang banger kills a little girl."

While the importance of culture and attitudes can't be denied, politics has played a deciding role in the few states passing gun control laws.

After New York Gov. Andrew Cuomo pushed through tougher firearms restrictions citing the Newtown killings, one poll showed his approval ratings, which had soared to 75 percent before the vote, down 20 percentage points.

In Colorado, the mass shooting at a suburban Denver movie theater last summer had lawmakers and the governor considering new gun legislation even before the massacre in Connecticut. Two days earlier, Gov. John Hickenlooper, a Democrat, told The Associated Press that "the time is right" to talk about gun control.

Still, in his January State of the State address, Hickenlooper only specifically called for universal background checks on gun purchases, and he appeared ambivalent about a measure limiting high-capacity magazines. But he ultimately followed through on a promise to legislators that he would sign such a measure, expending political capital in a state with a long tradition of gun ownership and libertarian leanings.

Every Democratic legislative vote was crucial in a Colorado, where the party controls both chambers and the new measures failed to get support from a single Republican. As some Democratic lawmakers appeared to waver in their support of new gun legislation, Vice President Joe Biden personally called a handful of lawmakers to urge them to support the new laws. Democratic Rep. Dominick Moreno said Biden "emphasized the importance of Colorado's role in shaping national policy around this issue."

The stakes in Colorado were made clear Wednesday when President Barack Obama traveled to Denver to praise the new laws that he said strike a balance, keeping firearms away from people who should not have them while protecting the constitutional right to own a firearm.

But the bitterness engendered by the new measures was made clear by more than a dozen Colorado sheriffs, all Republicans, who gathered a mile from Obama's appearance to slam the new regulations as ineffective and unconstitutional. Some have vowed not to enforce them.

'This is about taking a world of predators, a world full of wolves, and creating more sheep,' said Terry Maketa, the sheriff of El Paso County.

The tension was just as great, but different, in Connecticut, which is home to some of the country's largest gun manufacturers.

When lawmakers gathered Wednesday in Hartford to debate the bipartisan package of measures, gun rights advocates greatly outnumbered gun control supporters. Gun owners, some holding signs questioning the constitutionality of the proposals, stood in protest outside the state capitol and many packed the hallways outside the Senate chamber, occasionally chanting "No! No! No!" and "Read the bill!"

But Malloy's outspoken support for new gun control maintained pressure for passage, even as debate ground on in legislature long after similar measures were passed by lawmakers in neighboring New York.

A push for gun control by Maryland Gov. Martin O'Malley, a Democrat with presidential aspirations, also has been key to the chances for passage in that state. In neighboring Delaware, Gov. Jack Markell's call for action has also laid the groundwork for new restrictions with two months left in the legislative session.

But the furious debate and challenges faced by gun control advocates in many states are a reminder of just how difficult it is to tighten gun laws, even after the most horrific tragedy.

Those challenges were evident in 2007, when a gunman at Virginia Tech shot and killed 32, and Democratic Gov. Tim Kaine called for closing a loophole in the law allowing for private sales at gun shows without the same background check that licensed dealers are required to obtain. However, that proposal and other gun control measures have failed repeatedly in historically gun-friendly Virginia, where Republicans control the General Assembly.

It has proved true again in the months since Newtown, as lawmakers in Oregon gave up on a push to ban military-style rifles and high-capacity ammunition magazines amid a lack of support, choosing to focus instead on measures they hope have stronger backing. A Senate committee will take up their proposals for the first time Friday, including a universal background check requirement. Oregon already requires background checks at gun shows but not for other private sales.

And in Arizona, a staunchly pro-gun state where the 2011 assassination attempt of Rep. Gabrielle Giffords in Tucson left six dead and 12 wounded, the drive for gun control following Newtown has been a non-starter. With Republicans controlling the legislature and Republican Gov. Jan Brewer supporting most gun-rights proposals, Senate Democrats introduced 18 gun-related bills in the current session and all failed.

One Republican effort related to the Giffords shooting may make it through this year. That's a measure to provide $250,000 to expand a program to train teachers, first-responders and others to recognize people having a mental health crisis and intervene. Giffords' attacker, Jared Lee Loughner, suffered from mental illness.

The bill is sponsored by Rep. Ethan Orr, a Tucson Republican. He said Wednesday that although the bill, nicknamed Gabby's Law, didn't get a Senate hearing, he hopes the money to expand a program created after the shooting makes it into the state budget.

"The argument that I would make as a Republican is that if you're not going to look at gun control laws, people need to feel safer, and addressing mental health issues is a way to do that," Orr said. "I guess this is sort of our state's response."