"It's a bunch of BS," Sen. John Cornyn, who has worked alongside Collins for more than two decades, told USA TODAY.

Voters in the battleground state favored Senator Susan Collins, the Republican incumbent, over Troy Jackson, a Democrat, in several important areas, according to a New York Times/Siena poll.

Susan Collins super PAC and her campaign took money from a government contractor in exchange for helping to steer millions of federal dollars their way. Her office calls the allegations “categorically ...