In Search of the Real Casey

There was ease in Casey's manner as he stepped into his place;
There was pride in Casey's bearing and a smile on Casey's face.
And when, responding to the cheers, he lightly doffed his hat,
No stranger in the crowd could doubt 'twas Casey at the bat.
After Ernest L. Thayer wrote the classic ode to hero worship, Casey at the Bat, he was often annoyed about questions regarding the ownership and origins of his epic. Once the poem was popularized in vaudeville, other writers claimed authorship and many old ballplayers claimed to be Casey incarnate.
When the poem was first published by the San Francisco Examiner on June 3, 1888, a couple of active players could have fit in Casey's cap. Even if Thayer claimed to have made it up, it's fun to wonder if any historical figure provided grist for his literary mill.
In the early 1970s, a writer for the Detroit Free Press, George Cantor, had one theory. He wrote: "Isn't it probable that Thayer, writing in 1888, would have the previous season's championship team uppermost in his thoughts? ...The members of that team would have been squarely in the public eye. ...Isn't it entirely possible that the Mudville of Thayer's poem is actually Detroit, home of the 1887 world champs?"
He further argues that Samuel "Big Sam" Thompson, star right fielder of the Detroit team, and 1887's biggest slugger in the National League, was the corporeal Casey. Naturally, the Detroit writer had a vested interest in affirming a local birthplace for the literary character.
A much better case can be made for Mike "King" Kelly, the towering star of his day. Thayer, who was originally from Worcester, Massachusetts, and attended Harvard, was familiar with the fates of Boston's sports teams, and Kelly was playing for the Boston Braves at the approximate time the poem was written. In fact, after being traded to Boston from the Chicago White Stockings, the much-ballyhooed Kelly and his Braves suffered through two disappointing seasons in 1887 and '88. Kelly's grandiose failure during this period could have been prime fodder for a lampoonist like Thayer.
Cocky (and of Irish descent), Kelly certainly believed he may have been the model for the cocky (and of Irish descent) Casey. During his many vaudeville appearances, the baseball hero of his generation performed the standard as "Kelly at the Bat."