IDEMANDARECOUNT

Set to 2 different clues across 2 published puzzles, most often “Candidate's "This isn't over!"” — The New York Times, Sunday, 7 October 2007.

15 letters

Every clue on record, most used first

Candidate's "This isn't over!"once
The New York Times — Sunday, 7 October 2007
Mathematician's response to 17-, 22-, 51- and 58-Across?once
The New York Times — Wednesday, 3 August 2005