The massacre of children at an elementary school in Newtown appears to be profoundly swaying Americans' views on guns, galvanizing the broadest support for stricter gun laws in about a decade, according to a New York Times/CBS News poll.

As President Barack Obama tries to persuade a reluctant Congress to pass new gun laws, the poll found that a majority of Americans - 54 percent - think gun control laws should be tightened, up markedly from a CBS News poll in April that found that only 39 percent backed stricter laws.

The rise in support for stricter gun laws stretched across political lines, including an 18-point increase among Republicans. A majority of independents now back stricter gun laws.

Whether the Newtown shooting, with its 20 murdered first graders and six adults, will have a long-term effect on public opinion of gun laws is difficult to assess just a month after the rampage. But unlike the smaller increases in support for gun control immediately after other mass shootings, including the one after the 2011 shooting in Tucson, Ariz., that severely wounded Rep. Gabrielle Giffords, the latest polling results suggest a deeper, and possibly more resonating, shift.

In terms of specific gun proposals that are being considered, the poll found even wider support - including among gun owners.

The idea of requiring background checks on all gun purchases, which would eliminate a provision that allows some 40 percent of guns to be sold by unlicensed sellers without checks, was overwhelmingly popular. Nine in 10 Americans would favor such a law, the poll found - including 9 in 10 of the respondents who said that there was a gun in their household, and 85 percent whose households include members of the National Rifle Association.

A ban on high-capacity magazines, like the 15-round and 30-round magazines that have been used in several recent mass shootings, was supported by more than 6 in 10, and by a majority of those who live in households with guns. And just more than half of all respondents, 53 percent, said they would support a ban on some semiautomatic weapons.

"I'm from a rural area in the South, I grew up in a gun culture, my father hunted," Leslie Hodges, a 64-year-old graphic artist who lives in Atlanta and has a gun, said in a follow-up interview. "However, I don't believe being able to have a gun keeps you from thinking reasonably about changes that would keep someone from walking into a school and being able to kill 20 children in 20 seconds. I think that we can say, OK, we want the freedom to have guns in this country, but there are rules we can all agree to that will make us all safer."

The poll also gave an indication of the state of play in Washington at the outset of what is expected to be a fierce debate over the nation's gun laws, as the NRA and several members of Congress, particularly Republicans in the House, have criticized the gun control measures that Obama proposed Wednesday and have vowed to block them.

Americans said that they trusted the president over Republicans in Congress to make the right decisions about gun laws by a margin of 47 percent to 39 percent, the poll found.

The NRA, the powerful gun lobby, is viewed favorably by nearly 4 in 10 Americans, the poll found. All told, 38 percent said that they had a favorable opinion of the group, while 29 percent had a negative view and the rest had no opinion. The NRA was viewed positively by 54 percent of those with guns in their home, by 63 percent of people who own guns themselves and by 85 percent of households with members of the organization.

The survey underscored how common guns in America are: 47 percent of those surveyed said that they or someone in their household owned a gun, and another 31 percent had close friends or relatives who did. The top reasons cited for owning guns were for protection and hunting.

The national telephone poll was conducted by landlines and cellphones from Jan. 11 to Jan. 15, before the president announced his proposals to curb gun violence. It surveyed 1,110 adults and has a margin of sampling error of plus or minus 3 percentage points.

Some gun owners, like Sally Brady, a 69-year-old retired teacher who lives in Amissville, Va., explained in follow-up interviews why they would support some restrictions on ammunition or more thorough background checks of all gun buyers.

"I see no reason for high-capacity magazines if you want to go hunting," said Brady, an independent who owns a hunting rifle. "The purpose of hunting is sport, and you don't need a whole big bunch of bullets to shoot a deer or a squirrel. If you're that poor of a shot, stay out of the woods."

"I've come to think that background checks are a very good thing," she said. "We do have the wrong kind of people getting a hold of guns."

And Ronnie Talbott, a 44-year-old roofer from Mechanicsville, Md., said in a follow-up interview that while he would not support a ban on semiautomatic weapons, he believes "they definitely need to do away with high-capacity clips."

"I do favor a ban on high-capacity magazines that hold many rounds of ammunition," said Talbott, who is a Republican. "A clip with eight or nine bullets should be enough for protection because if you can't hit a person with nine bullets you must be a pretty bad shot."

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Despite the higher support for stricter gun laws, many Americans do not think the changes would be very effective at deterring violence. While most Americans, 53 percent, said stricter gun laws would help prevent gun violence, about a quarter said they would help a lot.

There was a stark divide on the question of gun laws between people who live in households with guns and those who live in households without them: While only about 4 in 10 people who live in households with guns said that stricter gun laws would be effective, 7 in 10 people who live in households without guns said that they would.

Other steps were seen as being potentially more effective. About three-quarters of those surveyed said that having more police or armed security guards would help prevent mass shootings in public places. And more than 8 in 10 said better mental health screening and treatment would help prevent gun violence.

Violence in popular culture is seen by a large majority of Americans, 75 percent, as contributing to U.S. gun violence, including about 4 in 10 who say it contributes a lot. There is a significant difference by age. Fifty-eight percent of older Americans say violence in popular culture contributes a lot to gun violence in this country; just 22 percent of respondents under age 30 agree.