Very popular in my grandmother’s household was Lawrence Welk. Corny or cheesy do not begin to describe him. Popular throughout a certain set does. He was marked by a signature expression he says he never used: wonnerful, wonnerful. Did I hear him say that. I think I did and he even titled his autobiography Wonnerful, Wonnerful.
So I turned my linguistic mind to this and thought about the upper Mid-West culture Welk came out of, heavily Scandinavian, and assumed Welk had spoken Swedish or Norwegian in the home. Aha! Norwegian generally pronounces an -nd- cluster by simplifying it to -nn-. Origin found!
Welk’s biography on Wiki says he did not speak English until he was 21 even though raised in North Dakota (surprise! surprise! – another TV byword). He spoke German! Oh well. German has no such amalgam of consonants into clusters that I know of and I took a whole class in the history of German.