I hate to say it ... Stephen King.
The movies Cimarron, Giant and Showboat definitely more well known than her novels on which they were based.
You need a good example? Edgar Allan Poe.
Sinclair Lewis has multiple titles listed - best-selling author of the 1920s - later a Nobel Prize winner in literature.
I'm not familiar with a lot of those books, admittedly. But most books in the top 10 for those years are notable enough, that they have their own Wikipedia article. "All Quiet on the Western Front" and "Gentlemen Prefer Blondes" in particular are highly influential works. They've had movies etc. made and are surely familiar titles to the average American, even if they may not have read them.