An immigration law overhaul passed by the U.S. Senate could increase spending by as much as $127 billion during the next decade but the cost could be much lower due to tax revenues from newly legalized workers, according to a congressional study reported by Reuters. House Republican opponents to the Senate bill on Tuesday pounced on the report by the Congressional Budget Office saying the legislation, which would create a guest worker program backed by President George W. Bush, comes "with a staggering price tag for American taxpayers." House Majority Leader John Boehner, an Ohio Republican, used the report to bolster an election-year push by House Republicans for immigration legislation that focuses only on border security and tough employer enforcement measures. "This is what House Republicans have passed," Boehner said in a statement. "And this is what the American people want and demand from their elected leaders." But Sen. Edward Kennedy, a Massachusetts Democrat who helped write the Senate bill, said the report shows the legislation also will generate more more federal revenues. "Providing legal status to the millions of men and women now living in the shadows will lead to increased wages and greater compliance with tax laws, generating more than $40 billion in revenue and offsetting most of the costs of the legalization reforms," Kennedy said in a statement. Leighton Ku, an analyst with the liberal Center on Budget and Policy Priorities, said the revenue effect would grow over time as newly legalized immigrants improve jobs and incomes. The Senate bill would require illegal workers seeking to legalize their status to pay substantial fines and pay back taxes as well as meet other requirements. "By the time people have done all these things, these are people who have become fairly self-sufficient," Ku said. The CBO estimated that the Senate-passed bill would increase spending by $48.4 billion over the next decade for federal food and health-care programs plus a refundable tax credit for low income workers. Spending for a new employer enforcement program plus more border patrol agents, detention facilities and construction of fencing along parts of the U.S. border with Mexico would total about $78.3 billion through 2016, the CBO said. But even conservative Republicans who are opposed to the Senate bill support these enforcement efforts. CBO noted that the Senate bill as written includes ambiguous language about employer liabilities for Social Security taxes that could result in a substantial loss in revenue over the next decade, some $79 billion. But when the "intent" of the legislation is taken into account, the result is a revenue increase of nearly $44 billion, CBO said. CBO also estimated that by 2016 more than 16 million people would take advantage of the guest worker program and provisions allowing illegal immigrants to adjust their status. That figure could grow to 24 million people by 2026, CBO said. -SPA