Washington (CNN) - It has been 150 years since the Civil War began with the first shots at Fort Sumter on April 12, 1861, and in some respects views of the Confederacy and the role that slavery played in the events of 1861 still divide the public, according to a new national poll.

In the CNN/Opinion Research Corporation Poll released Tuesday, roughly one in four Americans said they sympathize more with the Confederacy than the Union, a figure that rises to nearly four in ten among white Southerners.

When asked the reason behind the Civil War, whether it was fought over slavery or states' rights, 52 percent of all Americans said the leaders of the Confederacy seceded to keep slavery legal in their state, but a sizeable 42 percent minority said slavery was not the main reason why those states seceded....