As Democratic presidential hopefuls prepare to debate in South Carolina, it looks like the people of Myrtle Beach have already begun slingin' the dirt around.

Check out these pics of a 20-foot tall sand sculpture built to look like a Clinton-Obama-Edwards version of Mount Rushmore. We're told this monstrosity took 750 TONS (no- we're not kidding) of sand to create ... and a ton of elbow grease.

Now only if they would work that hard in the White House!