WASHINGTON - Efforts to allow illegal immigrants to eventually become legal U.S. residents were given little chance of winning congressional approval as the Senate began work on an election-year immigration bill. The legislation pits several Republican constituencies against each other. Social conservatives and governors say the tide of illegal immigrants is overwhelming their state budgets, but businesses say they want to keep them as a source of labor. Senate Judiciary Committee Chairman Arlen Specter, R-Pa., said he does not object to allowing illegal immigrants to earn legal permanent residency after several years of work, as proposed by Sens. John McCain,...