There was the following passage in New York Times’s (March 25) article that came under the headline, “Donald, This I will tell you,” written by Maureen Dowd:
“As The Times’s chief Washington correspondent Carl Hulse put it, the G.O.P. falls into clover with a lock on the White House and both houses of Congress, and what’s the first thing it does? Slip on a banana peel. Incompetence Inc.”
What does "fall into clover with a lock" mean? Is it a well-received turn of phrase? I googled for a definition of the phrase with no avail.