By A Long Shot Meaning

Example :   He couldn't keep up with me, not by a long shot.‎  He speaks better than he writes, by a long shot.‎1883, Mark Twain, Life on the Mississippi,  'Yes, I do recognize it now. It is the most wonderful thing I ever heard of; by a long shot the most wonderful--and unexpected.'1913, Jack London, The Valley of the Moon,  Well, he won't find Billy Roberts a sissy by a long shot.1920, Sinclair Lewis, Main Street,  See here: You KNOW you feel superior to folks. You're not as bad as I say, but you're not as good as you say--not by a long shot! What's the reason you're so superior?