Q: Given a sentence and two mentions from the text (arguments), indicate a phrase (a verb or noun phrase) that describes the relationship between the provided arguments.
Sentence: 'While Hillary Clinton was campaigning in North Carolina , Barack Obama was rejecting her call for another debate , moderated or not , before the North Carolina and Indiana primaries .', Argument/Subject 1: 'hillary', Argument/Subject 2: 'obama'
A:
campaign for