WASHINGTON (AP) — Efforts to delay implementation of changes in the federal flood insurance program have run into roadblocks on both sides of Capitol Hill.The leaders of the House Financial Services Committee say they are standing behind last year’s bipartisan legislation to put the flood insurance program on sounder financial footing even as the implementation of the law has sparked a chorus of complaints from constituents fearing spikes in premiums and plummeting home values.In the Senate, attempts to call a quick floor vote on legislation to delay the changes in the program — designed to force higher premiums on properties especially at risk of flooding — appear to face opposition from both Democrats and Republicans.Sen. Mary Landrieu, D-La., wants to add the measure to an unrelated defense policy bill, but Majority Leader Harry Reid, D-Nev., is restricting the ability of senators to offer unrelated amendments. Meanwhile, Republicans are unlikely to allow a vote that could give Landrieu, who faces a tough re-election bid next year, the chance to claim political credit.The curbs on taxpayer-subsidized flood insurance rates are a case study in what happens when Washington takes away a government-sponsored benefit that helps a relatively small group of people.About 1.1 million homeowners — or 1 in 5 in the program — have received taxpayer-subsidized rates and the government has financed about 60 percent of losses on their properties. Most people can retain the subsidies but can’t pass them along to people buying their home, a restriction that’s especially burdensome to lower-income older homeowners seeking to sell their houses.The changes also promise to make it unaffordable for people in chronic flood zones to keep their homes, and they have put a damper on home sales in areas where benefits extended to current homeowners can’t be passed along to prospective buyers.The quandary is especially felt by conservative Republicans torn between their philosophy of limited government and helping constituents facing sharply higher flood insurance premiums.