n. Euphemism for potentially scandalous information uncovered while researching a political opponent.
1997
Over the past decade, scandal has become an integral part of everyday politics. Largely as the result of a growing political industry known as "opposition research," allegations of wrongdoing by an opponent are dispensed by candidates for office as readily as position papers. No sane candidate would enter a race these days without a file drawer full of negative material on his or her opponent. In the heat of the campaign, the candidate can often brilliantly differentiate himself from his opponent with a negative ad that relies on some juicy bit of opposition research.
1997
No one runs campaigns in New Jersey — or anyplace else — without opposition research. Along with polling and advertising, it has become an essential part of any campaign that expects to succeed, fueling the rounds of attacks and counterattacks, negative ads upon negative ads. No charge is made or refuted without research.
1971 (earliest)
Two days later, an article appeared in a Washington newspaper describing the "opposition research" program nt Republican headquarters and noting, without naming her, that a young woman kept as close track of the Muskie effort as did the Senator's press secretary, Richard Stewart.