Possible Clues:

• Intel collected during a race
• __ research: some dirt-digging
• Research on a political rival, for short
• Tactical political research, for short
• Dirt on a campaign rival, briefly
• Partner's surgery evidently reversible?
• Colleague (informal)
• Research on a political rival, briefly
• Research into a political foe's weaknesses, in slang
• ___ research (info on a political adversary)