Financial disclosure reports show Republican U.S. Sen. John Ensign of Nevada has spent more than $550,000 in the past three months on legal fees.
The Las Vegas Review-Journal reported that Ensign wrote checks to a dozen law firms for himself and aides drawn into an ongoing investigation of his ethics.
The Senate Ethics Committee and the U.S. Justice Department are conducting investigations into whether Ensign broke laws or Senate rules in an attempt to cover up an affair.
Ensign's campaign finance report for the third quarter shows the expenditures left him with about $280,000 in cash on hand.
Ensign is up for re-election in 2012.
Information from: Las Vegas Review-Journal, http://www.lvrj.com