The four men arrested in January for their stunt to embarrass staffers in the New Orleans office of Sen. Mary Landrieu (D) are prepared to plead guilty, legal sources say, in return for reduced charges. Federal prosecutors today filed misdemeanor charges against the four. James O’Keefe, who became a media sensation last year for his videos involving ACORN employees, and three others were charged with entering federal property under false pretenses. Two of them went to her office pretending to be telephone repairmen. The charges said all four were in on the plan. Because the charge is a misdemeanor — and not a felony — the maximum sentence is six months in prison and a $5,000 fine. The government dropped its earlier, more serious, charges of tampering with government phone lines.