A bipartisan group of senators urged the Obama administration Thursday to investigate reports that businesses are using a visa program to replace American workers with cheap foreign labor.The unlikely coalition, led by Republican Sen. Jeff Sessions and Senate Democratic Whip Dick Durbin, sent a letter to the Department of Homeland Security, Department of Labor and Department of Justice, asking them to investigate businesses, such as Southern California Edison, suspected of abusing work visa programs to avoid paying relatively high wages to American workers.SCE has reportedly been laying off hundreds of American workers and replacing them with foreign workers who hold an...