Former President George W. Bush reacted to GOP Sen. Lindsey Graham's death on Sunday. 

"Laura and I were saddened to wake up to the shocking news of Senator Lindsey Graham's death. He was a knowledgeable Senator who understood how the world works and how important America's international engagement is to resist tyranny," Bush said in a statement.

"He was a kind and funny man who loved our country and loved serving it. South Carolina was fortunate to have such a committed public servant in its corner. And I was fortunate to have known Lindsey Graham," he added.