Washington (CNN) -- Describing the billions of dollars in contracts and services handled by the General Services Administration as a den of temptation, senators from both parties on Wednesday called for the agency at the center of a spending scandal to clean house as it roots out corruption. "The party's over," declared Democratic Sen. Barbara Boxer of California, chairwoman of the Senate Environment and Public Works Committee, at one of four congressional hearing so far this week on the controversy that has embarrassed the Obama administration in an election year. Speaking to GSA Inspector General Brian Miller and Acting Administrator Dan Tangherlini, Boxer said the panel "will support you and encourage you to clean house" at the vast federal procurement agency.
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NEW: Inspector General Brian Miller says his office is finding more possible problems
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Democrats note past GSA scandals and positive steps by Obama appointees
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Republican Sen. James Inhofe says the GSA is a likely home for corruption
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The reported abuses include wasteful spending and violations of regulations
"What is so outrageous about this is how these bad apples, very bad apples, perhaps criminal apples, have sullied the reputation of very good people," @placeholder said, adding, "don't underestimate this job you have in terms of shaking this tree and letting these bad apples fall."