According to Ancestry.com, it is Smith with 81 records with that name. In the 2000 census there were 2,376,206 Smiths.
"Surnames began to come about in the Middle Ages, when people were often identified by their trade. Just about every village in Britain had a smith, usually a blacksmith, who made horseshoes, plows, swords, armor, and other needed items. These workers were skilled and had status in the community, which contributed to their wide usage. Some names were once more specific, with people called Combsmith or Smithson, and were later shortened to Smith."
Here's something I see in online stories like this one. In the middle of an article one or two words are highlighted as a link for no good reason. In this case it is the word, contributed. Why? When you click the word contributed, you get an article on Smith family history not the meaning of contributed. Why not highlight the name Smith?