The best and most correct answer among the choices provided by the question is the second choice "He let his party campaign for him."
In 1860, Lincoln won the party's presidential nomination. In the November 1860 election, Lincoln again faced Douglas, who represented the Northern faction of a heavily divided Democratic Party, as well as Breckinridge and Bell.
I hope my answer has come to your help. God bless and have a nice day ahead!
