The Journal’s parent Dow Jones operates the Factiva news service, which offers a voluminous database of sources including newspapers, magazines and television news transcripts, among others. The archive goes back decades. A search for “Republicans pounce” conducted via Factiva returned 245 entries. But no fewer than 311 stories popped up when this column entered the search term, “Democrats pounce.”
This hardly settles the question, but at least it’s one data point. Background here.