The home of the Commander in Chief is no stranger to the paranormal. Jimmy Carter once reported seeing a UFO. Nancy Reagan regularly cosulted astrologists. The ghost of Abigail Adams has been seen more than once, hanging wash out to dry. Most commonly reported, and by some quite notable witnesses, is the ghost of Abraham Lincoln. It has been seen so often, it has came to be referred to as simply the White House Ghost.
While in office, Lincoln and his wife Mary dabbled in Spiritualism. They routinely held séances to try and contact their son Willie, who had passed away in the White House. President Lincoln also received advice from spirit visitors, such as the specter of the deceased Massachusetts Senator Daniel Webster, who urged him to continue his fight to free the slaves.
Just prior to his assassination, Lincoln encountered a doppleganger-like figure in a mirror. Seeing one's doppleganger is in some cultures an omen of impending death. While lying on a couch Lincoln saw his reflection as having two distinct faces. He rose and went to the mirror, finding his reflection normal. Returning to the couch, he saw the strange reflection a second time. He said this time, one of the faces were noticeably paler than the other. A few days later he attempted to recreate the event. Sure enough, it came back. After several more attempts, however, Lincoln was never able to make the doppleganger image reappear. He tried unsuccessfully to have it appear before his wife. Mary was very concerned. She saw the doppleganger as a sign that Lincoln would be re-elected to a second term, but would not live to see the end of it.
On the day of his assassination, John Kennedy remarked to his wife and friends, "If someone is going to kill me, they're going to kill me." Several eerie coincidences connect the Lincoln and Kennedy assassinations. See the video below for more on that. Days before his own assassination, Lincoln told of a dream he had, in which he found himself wandering about the White House. He could hear sobbing. Following the noise, he entered the East Room to find a body laid out before mourners. Soldiers stood guard around it. Upon asking who was dead, a soldier replied, "The president, he was killed by an assassin." A full account of the dream can be found here: Lincoln's Dream
Paranormal events linked to Lincoln were reported frequently during FDR's administration. It's been theorized this is related to both presidents being in office during times of great war. Eleanor Roosevelt used the Lincoln Bedroom as a study and although she never saw an apparition, said she often felt as though she was bring watched and believed it to be Lincoln's presence. A clerk for the Roosevelt administration saw Lincoln's ghost sitting on the edge of a bed pulling his boots off.
Queen Wilhelmina of the Netherlands was spending the night in the White House when she was awakened by a knocking on her door. She answered the door to find the specter of Abraham Lincoln standing before her. She was so frightened she fainted. When she awoke the ghost was gone.
During WWII Winston Churchill was spending the night at the White House. He liked to take a bath and have a cigar before retiring to bed. Retuning to the adjoining bedroom in his birthday suit, Churchill discovered Lincoln's ghost standing by the fireplace. “Good evening, Mr. President. You seem to have me at disadvantage,” he said, as Lincoln was fully dressed.
Several other Presidents, First Ladies, and White House visitors have seen or felt the presence of Abraham Lincoln. His ghost is also said to be spotted at Ford's Theater where he was shot, and in Springfield, Illinois at his gravesite. A ghost train, identical to the one that carried Lincoln's body across much of the country following his death, is said to be seen in several places along it's original route, sometimes carrying a skeletal band playing music that cannot be heard.