He was an unsuccessful candidate for the United States Senate in 1885. When he was defeated for reelection in 1886 to the 50th United States Congress Congress, it came as something of a shock to his party, but to knowledgeable Illinois observers, the real shock was that defeat had come so late: Republicans had kept fiddling with his congressional district's boundaries to make it more firmly Republican, and to their dismay found that however the voters went in presidential races, they still went for Morrison in the congressional race. In 1886, however, the decisive factors may have been two: great tubs of money flushed into the campaign by the iron and steel industry's high tariff lobby and opposition from the Knights of Labor, itself committed to tariff protection.