The walking and talking Abraham Lincoln memorial (typically referred to simply as Abraham Lincoln or Abe) is the titular character of Abe Lincoln Must Die!.
After Max decapitates the Puppet President, Chuckles initiates the next stage of his plan by bringing Lincoln to life (via installing hydraulics in the Lincoln memorial). However, Max opposes his presidential run and eventually beats him in the election. Infuriated, Lincoln goes on a rampage hypnotizing many people and causing widespread damage. This rampage is brought to an abrupt end when Sam & Max reduce his body to rubble by hitting him with an ICBM. (His head lives on to return in later episodes.) Strangely enough, when his body is reduced to rubble none of his robotic components are visable.
During the election, Sam and Max caused a scandal by making Sybil think Abe wanted to date her, which he squarely rejects. But after being rid of Chuckles' influence, he does find himself interested in her. When they meet him again at the Blister of Tranquility in Bright Side of the Moon, they help him get another chance. Sybil and Abe's shaky relationship eventually leads to the two of them getting married at the end of Sam & Max Season Two.
Abe returns in the final episode of Season Three. He leads an army of Maimtron 9000's against the demon Max. He somehow has regained his body. His wife Sybil is now pregnant. He was last seen in the cloning chamber as Mama Bosco attempts to revive Max.
Abe seems to have all the memories of the historical Abraham Lincoln and apparently believes he is him. Whether this is due to his programming or whether he has Lincoln's memories is unknown.