Well, found a couple before Lincoln:
In 1776 during the Revolutionary War, a plot was uncovered to kidnap and murder General George Washington. The conspiracy involved the mayor and governor of New York as well as his personal bodyguard, Thomas Hickey. The latter was found guilty of treason and publicly hanged on June 28 in view of nearly 20,000 spectators. Washington remarked that the execution should set an example of how mutinous officers are rewarded.
ANDREW JACKSON
The first assassination attempt of a president occurred in 1835 when Richard Lawrence, 32, approached Andrew Jackson on a Washington street corner and aimed a derringer at point blank range. The gun miss-fired, but much to the shock of the president, Lawrence produced another derringer and attempted the assassination again. The second gun also miss-fired. Lawrence was later declared insane and died in an institution.
Following the attempt on Jackson, Vice President Martin Van Buren regularly carried two pistols while presiding in the Senate.
Some one hundred years later the Smithsonian Institute acquired the derringers and tested the weapons in an attempt to find the cause of the miss-firings. Both guns discharged on the first try. The odds of both derringers miss-firing in 1835 were calculated at one in 125,000.
"High time we made a stand and shook up the views of the common man" - Tears for Fears