Published: Apr 22, 2011 12:06 AM EDT
Updated: Apr 21, 2011 9:06 PM EDT

LAS VEGAS (AP) - Nevada Sen. John Ensign announced he will resign amid an ethics investigation.
 
Ensign said Thursday he will send Vice President Joe Biden a letter Friday making the resignation official. He said he has not violated any laws or rules, but said he could no longer subject his family, friends and constituents to further investigations.
 
The Republican, who is under investigation by the Senate Ethics Committee, announced in March that he would not pursue re-election.
 
The 52-year-old acknowledged in June 2009 that he had an extramarital affair with Cynthia Hampton, a former member of his campaign staff, and that he had helped her husband, Doug Hampton, a member of his congressional staff, obtain lobbying work with a Nevada company.

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