This market resolves positive if a major-party candidate for US Congress in the 2022 midterm elections contests the results of the election they were in, including:

If a candidate says they believe the election was fraudulent, but concedes on time and doesn't make any attempt to fight it, that will not count as contesting the election results for purpose of this market. If a candidate's supporters take some action, but the candidate doesn't positively endorse it, that won't count as a positive resolution.

This market resolves negative if nobody has met any of these criteria by December 1 or three days after the mainstream media calls the results of the last race, whichever happens later.

UPDATE: Added the words "major-party". If you feel like this unfairly affected your investment, please contact me and I will try to reimburse you. Sorry!