Simplify the following text for a Grade 10 native English-speaking person.
Original: When President Andrew Johnson , who had no Vice President , was impeached and tried in 1868 , Senate President pro tempore Benjamin Franklin Wade was next in line to the Presidency .
Simplified: Many people still think of the President pro tempore as de facto president of the Senate . During President Andrew Johnson 's impeachment trial in 1868 president pro tempore Benjamin Wade was the first person in the line of succession .