The Australian ballot is the secret ballot, and it seems Louisville was the first city in the U.S. to use it. Some of the stuff described here is really amazing. I'll quote liberally, but the best stuff is in the book:
Louisville is not a location that one normally thinks of as a cesspool of corruption. Quite the contrary, as the city that pioneered the Australian ballot, it is usually seen as progressive and mostly immune from the problems that plagued so many other areas.
...After Reconstruction, Louisville was Kentucky's largest city and the eighteenth largest in the nation. ...The city relied heavily on Ohio River commerce for its economic base and had a cosmopolitan mixture that included Democratic Irish Catholics and Republican African-Americans. Politically, the Democratic party effectively controlled the city as the memories of the Civil War persisted, and the winner of the city's Democratic primaries was effectively the winner of the general election in November.
Throughout the 1880s, Louisville had experienced a series of fraudulent elections. To correct the problem of repeaters, a Louisville representative, Albert Stoll, introduced a bill in the Kentucky legislature calling for mandatory registration in Louisville. ...His bill became law in 1884, but it had no effect on reforming the process.
...One of the members of the 1887 committee was Arthur Wallace, a Louisville state representative. After reading an article on the new secret ballot system used in Australia, Wallace approached some area judges to see whether a law mandating such a system could pass constitutional muster in Kentucky. Wallace's bill could not be applied to the entire state without amending the state constitution, so it affected Louisville's municipal contests only. When the "Wallace Election Bill" quietly became law in February 1888, Louisville became the first municipality in the nation to adopt the new voting method.
...By the 1890s, John Whallen, a young burlesque theater owner, became the acknowledged king of Louisville's Democratic party. ...Whallen once boasted that his burlesque theater was the real center of the city's political apparatus, a place he once described candidly as "the political sewer through which the political filth of Louisville runs."
...After temporarily losing control of city government in the mid 1890s, Whallen reappeared, helping his hand-picked candidate win the mayor's race, due in large part to a new method employed by followers of Whallen: police intimidation of African-American voters. When a prominent African-American attorney attempted to vote, he was confronted by a police officer who told him, "I have worn out four billies and I will wear this one out on you." Less violent means, such as clerks slowly checking registration lists, meant those wishing to vote in the heavily African-American Ninth and Tenth wards often waited hours to cast a ballot. Of course, many found that before they had reached the front of the line, the polls had closed. ...Without the strong arm of the police, Whallen's machine could not have controlled Louisville's elections.
Whallen's cronies used other methods to fight the Republican turnout among African-Americans. By 1900, the 28,651 African-Americans living in Louisville comprised nearly fourteen percent of the city's population. Although Democrats had not legally disenfranchised African-Americans in Kentucky as they had throughout the Deep South, electoral intimidation and fraud remained potent tools in the hands of people such as Whallen. The historian George C. Wright wrote that Whallen hired black "shadies to form Negro Democratic Clubs, which were little more than instruments of organized intimidation of African-American voters, and concluded that "Negro thugs, as much as anything else, kept blacks from viewing the Democrats as a respectable party." When that tactic failed, Whallen resorted to the well-tested strategy of appealing to white supremacy and the fears of what Republican victories might bring to Louisville's racial climate.
By the early 1900s, then, John Whallen directed the Democratic machine in Louisville. But he was not without his opponents among the city's Republican stalwarts, as well as a number of Democrats who resented Whallen using the city's political apparatus to increase his personal wealth and power. ...With the 1903 election fresh in their minds, disenchanted Democrats joined with angry Republicans to form a fusionist party which, with its combined strength, hoped to defeat the Democratic mayoral candidate, Paul Barth, in the upcoming 1905 election.
...The Whallen machine employed area criminals to intimidate African-Americans from registering, and understood that the illegal registration of "repeaters" had a dual effect: It could potentially crowd off from the rolls many legal voters, thus making the job of controlling the election that much easier. ...When challenges were made by Fusionists to some questionable Democratic attempts to register, a Louisville police officer named Roman Leachman threatened the challengers on several occasions. Leachman shouted that if an official "refuses to register another man, I will smash him in the head and kill him and I will come and throw his carcass into the street; he doesn't amount to anything." One official meekly inquired if Leachman was overstepping his bounds, and in revealing language Leachman underscored the reason for the police presence at the registration booths: "To hell with you. This means nothing to your crowd, and means four years for me, and of course I am going to look out for my own interests." The next day, Fusion workers were simply thrown out of their polling places and Democratic officials seized registration books and completed them in private.
...In order for all of the corrupt figures in the Louisville election to do their jobs properly, money was a necessity. ...Fred R. Bishop, treasurer of the Democratic campaign fund, later described how he went about raising these funds. Candidates for various city offices were to contribute ten percent of their current city salary, while police officers contributed according to their rank... After acquiring the money from Bishop, the ward captains knew what to do with it. They spent part of their money paying city police officers and firefighters to take the day off to perform various chores in helping Democrats. More than twenty percent of the city's firefighters claimed they were sick on Election Day and were put to use on behalf of the Democratic campaign.
...In the 38th Precinct of the Third Ward, three armed men simply took the ballot box at gunpoint, loaded it on a wagon and carried it away. ...In the Twelth Ward, a former member of the fire department and devout Whallenite, John Barry, pulled a pistol on an election worker and demanded the ballot books. With the help of three policemen, Barry took the books to another location, swore in his own election workers, and proceeded to stuff ballot boxes with hundreds of his own votes.
Some of the abuses Campbell describes are just amazing by modern standards. At one point during registration, a worker accepted a glass of lemonade from a saloon owner and passed out; he realized he'd been drugged when his registration books turned up with a large number of forged names in them. Barth won the election, but in May 1907, the election results were overturned in court, and the governor named an interim mayor and municipal officials. But Whallen's candidate won for mayor in 1909 with a viciously racist campaign.