You don't remember correctly, and probably should have looked it up. Hamlin was Lincoln's Vice President during his first term, but made no speeches at Gettysburg.
The orator who spoke at Gettysburg before Lincoln's two-minute speech (the one that's now remembered) was Edward Everett, at various times Governor and Senator from Massachusetts, Ambassador to Great Britain, and Secretary of State.
I should have known someone would be faster with the correction than I! ;)