Former Rep. Joe DioGuardi (R-N.Y.) has decided to challenge Sen. Kirsten Gillibrand (D-N.Y.), according to the Associated Press.
DioGuardi will announce his candidacy Tuesday at Grand Central Station.
DioGuardi was first elected in 1984 and defeated by Rep. Nita Lowey (D-N.Y.) in 1988. His former district just north of New York City is solidly Democratic.
The Republican is the father of Kara DioGuardi, a judge on American Idol.
Former Bush adviser Dan Senor is reportedly considering a GOP challenge to Gillibrand. Billionaire Mort Zuckerman was also considering a bid but has decided against it.