Altschuler spokesman Rob Ryan says the candidate has decided against forcing a hand recount in the 1st Congressional District. Bishop has a 263-vote lead. That was the last undecided House race in the nation.
Altschuler called Bishop early Wednesday to concede.
Ryan says about 977 absentee ballots are left to be counted. More than 194,000 votes were cast.
This will be Bishop's fifth term in Congress.