Some of these last names are legitimate voters. My grandmother, who once voted reliably Republican but probably now votes illegally for Democrats, had a unique last name. Her husband came of America from a small ethnic group in Europe with the types of names that usually got misspelled at Ellis Island. He died in the war; of their three daughters, two married and moved away, and a drug addict killed the third. They had no sons. So she had no family on her late husband’s side who lived in the state.
My grandmother recently deceased, which means that she should cease to vote. But when she lived on this earth, she voted with her “one-of-a-kind” last name. And those votes should count. After she deceased, she perhaps moved in spirit posthumously to Pennsylvania, even though her body is still interred in a cemetery in a different state, registered to vote, and voted Democrat from the grave. If she accomplished that feat, then her votes should not count.
There assuredly are a relative few. It should not be hundreds of thousands of people. I have multiple friends with such mis-spelled last names, but none of them are unique, as there are others with names mis-spelled the same way. It is especially the case for more recent years.
Some of the examples will simply be mis-spelled names. That said, there would seemingly be thousands of such, maybe even low tens of thousands, but it doesn’t seem likely hundreds of thousands without even duplicating others mis-spellings.