Law firms with public advocacy businesses in the Beltway have seen their revenues buoyed by a volatile midterm season in what otherwise would have been a quiet time while Capitol Hill braces for November elections.

In past years, midterm elections have often prompted a dip in lobbying revenues for the third and fourth quarters, as legislation stalls ahead of potential changes in the congressional balance of power. This year, however, many firms have not seen such a trend, according to quarterly Lobbying Disclosure Act filings made public Wednesday.