William Wade Dudley was the son of Rev. John Dudley, a well-known Congregational minister in Weathersfield whose sermons were widely reprinted, a graduate of Yale Seminary, a sometime missionary to the Choctaw Indians and a descendant of William Dudley, one of the earliest settlers of Guilford, Connecticut in 1639. Dudley's mother was Abigail Wade, a granddaughter of Col. Nathaniel Wade, a staff officer to General George Washington during the Revolutionary War.
After studying at Phillips Academy, Danville in Vermont, and at Russell Military Academy in New Haven, Connecticut, he joined the army as captain of the Richmond City Greys in the 19th Indiana Volunteers of the famed Iron Brigade. After losing 79 percent of his men at the Battle of Gettysburg, and having his right leg amputated on the field, he served as an army inspector and judge advocate.
Following the end of the war he became a civilian lawyer in 1870, then the U.S. marshal for Indiana in 1879, commissioner of pensions under appointment of Presidents James Garfield and Chester A. Arthur in 1881. In 1888 he was appointed Treasurer of the Republican National Committee. He returned to practicing law in 1887. He married in 1864.
In 1888 having been made Treasurer of the Republican National Committee, Dudley was involved in the 1888 elections and one of the most intense political campaigns in decades, with Indiana dead even between the Democrats incumbent, President Grover Cleveland – and the Republican challenger Benjamin Harrison.
Although this job did not strictly involve him in state politics, Dudley wrote a circular letter to Indiana's county chairmen, telling them to "Divide the floaters into blocs of five, and put a trusted man with the necessary funds in charge of these five, and make them responsible that none get away and that all vote our ticket," and promising adequate funding for this.
Unfortunately for the Republicans, the Democrats managed to get hold of the letter and they distributed hundreds of thousands of copies in the last days of the campaign. Given Dudley's unsavory reputation, few people believed his denials.
The attack on "blocs of five" with the suggestion that pious General Benjamin Harrison was trying to buy the election enlivened the Democratic campaign and stimulated the nationwide movement to replace ballots printed and distributed by the parties with the secret 'Australian ballot'. Benjamin Harrison's electoral votes topped Cleveland's to win the election.