Abraham Lincoln was born on February 12, 1809 and John F. Kennedy was born on May 29, 1917. No similarity there between the two. Lincoln was elected the 16th POTUS while Kennedy became the 35th POTUS. Still nothing coincidental about those facts.
Lincoln was elected to Congress in 1846 and JFK was elected in 1946. Exactly (well in years) one hundred years apart Lincoln and Kennedy were elected to the House of Representatives. Representative Lincoln served only one term in the House after being a part of the Whig Party's opposition to President James K. Polk and the Democratic Party's war win against Mexico, making the United States a continental power. Representative Kennedy on the other hand went on to win reelection to his House seat two more times and then in 1952 wins the race for Massachusetts' open senate seat in the U.S. Senate, the other house of Congress.
Senator Kennedy went from the Senate to the White House in 1960, whereas Lincoln won the presidential election of 1860 without having served in elected politics since he left the House in 1849, when Polk was leaving office and Zachary Taylor was entering office. One hundred years apart both became president of the United States. They were both challenged by an incumbent, and youthful, vice president in the General Election, John C. Breckinridge in 1860 and Richard M. Nixon in 1960, both would announce their loss to Lincoln and Kennedy, respectively.
President Lincoln had to deal with States in rebellion from the start of his term and his goal was first and foremost to preserve the Union of States before the Civil War took on the responsibility of freeing the enslaved blacks in the South. He was president during the Civil War, while JFK was a president that served during the Cold War, another "C"-"W" initialed event. His hundred year counterpart would become associated with Civil Rights as well and his death would help push Civil Rights legislation through the Congress by his successor one hundred years after the Civil War ended. Essentially the Civil Rights that Lincoln began fighting for don't come to until almost one hundred years after his death.
As president, they both had young children in the White House, or during Lincoln's time, the Executive Mansion. Their wives also lost a child while living in the presidential mansion. Mary Todd Lincoln, and the president, lost their youngest William to an illness at the age of 11, where Jack and Jackie Kennedy lost their child, Patrick, two days after being born. The two died one hundred and one years apart.
Both presidents had secretaries named after the other. President Lincoln had a secretary named Kennedy and President Kennedy had a secretary named Lincoln.
But there's more connections.
John Wilkes Booth shoots President Lincoln while he, his wife and the Rathbones (such a 19th Century-sounding name) watch "Our American Cousin" from box seats at Ford's Theater. Why the sketch artist just sketched and didn't help is one of history's greatest unsolved mysteries so says the ghost of Robert Stack.
Lincoln was assassinated in 1865 and Kennedy was assassinated in 1963, almost one hundred years. Almost. But they were both shot on a Friday while sitting next to their wives. Both were shot in the head. They were with another couple. The Lincolns went to Ford's Theater with the Rathbones and the Kennedys rode with the Connallys in an automobile named Lincoln. Both males that were with the president when they were shot were both injured and survived the attacks. The presidents were shot by men from the South. One was born in 1838 and the other born in 1939. The assassins were known by their full name, three names made up of 15 letters, John Wilkes Booth and Lee Harvey Oswald. Booth fled a theater for an abandoned warehouse, whereas Oswald did the opposite, he went from a warehouse to a theater. Both Booth and Oswald were shot and killed before their trial.
Both presidents were succeeded by Southerners who were their vice presidents. Both vice presidents were named Johnson and born one hundred years apart, 1808 and 1908 Tennessee's Andrew Johnson was loyal to the Union and put on the Union Party ticket with President Lincoln in 1864, a ticket made up of a Republican and a Democrat. Johnson became the 17th POTUS the day after Lincoln was shot and three hours after he died. Texas' Lyndon Johnson ran with Kennedy in 1960 and was sworn in as the 36th POTUS the day JFK was shot and killed in Dallas. Johnson-17 would go on to become the first impeached POTUS but survived the trial in the Senate by one vote in a battle to control Reconstruction of the South. His impeachment would weaken the executive branch, which was strong during Lincoln's terms, for the rest of the 19th Century. Johnson-36 would go on to win a landslide election of his own in 1964 but while he had success with Civil Rights and hoped for a great society, Johnson-36 eventually lost favor with the American people and his party as reelection in 1968 seemed impossible thanks to the longevity of the Vietnam War and his mishandling of the Cold War's proxy hot war.
All of this is nothing but historical coincidences. Nothing more. These comparisons between the two American presidents has been going on since the mid-1960s, more than likely.