The Senate's defeat last week of firearms restrictions underscored the nation's shifting demographics and a pronounced divide on the gun issue between Americans in rural areas and residents of suburban enclaves, like Quakertown, outside Philadelphia. Packed with married women and political independents, vote-rich communities like these are starting - in the wake of a string of shooting massacres - to act more like urban centers that long have been concerned with the threat of local gun violence and have favored stricter laws. Those include the expansion of background checks, viewed by gun control advocates as a way to prevent criminals and the mentally ill from buying firearms. Like most Pennsylvania voters, Lisa Inglis, 43, a stay-at-home mom of two from the Philadelphia suburbs, is a supporter of expanded checks of gun buyers, part of the legislation defeated last week. She said she was very disappointed by the Senate action, though she also questioned whether such measures would prevent many crimes. The reality hits you that nobody can keep anybody safe. You really depend on the stability of other people's thinking. You just hope for the best," said Inglis, eating at John's Plain & Fancy Diner in Quakertown, about 45 miles north of Philadelphia. Voters like her in suburbs like this are a big reason why a handful of Republican lawmakers broke ranks with the GOP last week to support the expanded checks, raising the possibility that gun control could end up becoming more acceptable to other Republicans as suburbs in swing-voting states swell and push farther into rural areas where people cherish their gun rights. Four Republicans backed the proposal, including three - Sens. Patrick Toomey of Pennsylvania, Mark Kirk of Illinois and John McCain of Arizona - where suburbs play a strong role in their home states' politics. The proposal also won support from Democrats such as Virginia Sens. Mark Warner and Tim Kaine and Colorado Sens. Michael Bennet and Mark Udall, two states that are home to many hunters living in rural areas - but also to booming suburbs outside Washington and Denver. To be sure, rural interests still play a powerful role in Congress, and the gun vote showed how small states can shape the debate. Democrats representing rural states bucked members of their party and President Barack Obama to help scuttle the legislation. Among Democrats, five opposed the plan, including rural state lawmakers like Mark Pryor of Arkansas, Mark Begich of Alaska and Max Baucus of Montana, all of whom face the voters next year. Polling bears out the geographic divide. In the months since the deadly Newtown, Conn., elementary school shooting, polls showed an overwhelming support for expanding background checks and strong sentiment for tighter gun measures among women. An Associated Press-GfK poll this month found that 52 percent of people living in suburban areas supported stricter gun laws compared with 41 percent rural residents. An additional 44 percent who live in rural areas say gun laws should remain the same, 13 percent think they should be made less strict. The poll found that 58 percent of women favored stricter gun laws, compared with 41 percent of men. The difference held up across party lines, though 34 percent of Republican women supported stricter gun laws compared with 80 percent of Democratic women. Republicans said many GOP members were challenged by the larger context of Obama's agenda - including likely votes ahead on immigration and growing support in the nation for gay marriage. They can't go all in. They have to pick and choose," said Chip Felkel, a South Carolina-based Republican strategist. The NRA doesn't want to give an inch on anything because they think it's the beginning of the slide. Toomey's role offered an apt case study. A reliable conservative and former head of the free-market advocacy group Club for Growth, Toomey joined forces with West Virginia Democrat Joe Manchin to push for expanded background checks. Toomey has garnered strong ratings from the National Rifle Association but faces re-election in 2016, a presidential year in which elections in his home state tend to pivot on voters in the Philadelphia and Pittsburgh suburbs. Inglis, of Quakertown, calls herself a "liberal Republican" - she voted for Obama twice and Toomey in 2010 - and she credited Toomey with picking "the right issue to break out of his mold on." She said it made her view him as a pragmatist working to solve problems. Bob Linquist, 73, a retired utility worker from Quakertown, used to belong to the NRA but dropped his membership because of the group's views on military-style assault weapons, which he believes do not belong in private hands. Linquist, a Democrat who sometimes votes Republican, said he supported Toomey's position on background checks even though he questioned whether it would solve the problem and thought it was politically calculated. Politicians don't always stand up for their country or ideologically what's right or morally right. They worry about their job," Linquist said. Toomey sought to explain his position to a gathering of conservatives during the weekend. "My hope is that we can agree to disagree on this and move on to the many, many areas on which we agree," he told the Pennsylvania Leadership Conference in Camp Hill. Terry Madonna, a pollster and political scientist at Franklin & Marshall College, said that with more than 9 in 10 Pennsylvanians supporting universal background checks, Toomey staked out a very safe political position. He said Toomey's bill was probably designed to appeal to swing voters in suburban Philadelphia, noting that "the largest area of support for gun control measures comes from the Philly suburbs." The pressure points on the bill were found in the suburbs. A gun-control group backed by New York Mayor Michael Bloomberg focused its persuasion campaign - with mixed results - on areas represented by Republicans that include pivotal suburbs. The organization, Mayors Against Illegal Guns, aired ads in Philadelphia, Phoenix, Atlanta, Las Vegas and parts of Ohio. Despite the measure's failure, some Democrats view it as evidence of how the issue has taken hold of suburban voters. Pat Toomey is no moderate. The fact that he's doing it in the state he's from tells you the power of the suburbs," said Rep. Gerald Connolly, D-Va., who represents a suburban district outside Washington. Thomas reported from Washington. 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