Under the original federal Constitution, state legislators, not the voters, elected U.S. senators, and the Kentucky General Assembly was to choose a replacement for outgoing senator Isham Talbot in December 1818. Johnson was considered a strong contender if he entered the race, and in October he let it be known through the press that he would accept the Senate seat if the General Assembly elected him. On December 18, 1818, legislators chose William Logan over Johnson, 67–55. Newspapers noted that the former congressman had never officially declared his candidacy, and that Johnson's political friends intended to nominate him for governor in the 1820 election.