As readers of this space are aware, alternative voting ideas such as ranked choice voting and all-party primaries are drawing new interest. In fact, America has a rich if sporadic history of electoral innovation—from Nebraska’s one-off nonpartisan legislature to the ventures in proportional representation that went on in many cities in the first half of the twentieth century.

One excursion that might be worth a second look, at least as object lesson, is Illinois’s longstanding use of cumulative voting, an arrangement that does well at protecting minority political interests at the cost of inviting gamesmanship. For more than a hundred years, until 1980, members of the Illinois lower house were elected in three-member districts, with the distinctive feature that individual electors could divide their three votes among three different candidates, cast all three for the same person, or allocate them two-and-one.

Perhaps the most salient feature of this arrangement was the opening it gave for a sizable but less-than-majority bloc of voters to win one of the three seats in a district by concentrating its votes. Sometimes the relevant voter concentration was racial or ethnic, as when a black candidate managed to secure a seat in a white-majority district.

Often, though, it was political. Disciplined triple voting could enable Republicans to pick off some seats in predominantly Democratic Chicago, while Democrats used the same technique to win some seats downstate.

Not surprisingly, this selection method gave the Illinois lower house a distinctive texture. For example, its GOP caucus included members from Chicago who could speak knowledgeably about city problems, just as there would be many Democratic members with firsthand experience of small-town and rural matters.

Voters would often confer seats on members of different factions within the local majority party, fostering intra-party diversity. Thus, a mostly Democratic district might elect one liberal Democrat, one Democrat of more moderate leanings, and one Republican, with a more conservative and Republican district doing the opposite.

As a Chicago Tribune account put it, the era of cumulative voting “produced some of the best and brightest in Illinois politics,” including many distinguished reformers in a state long known for tough machine politics.

The late Rep. Abner Mikva, who went on to serve as a federal judge, recalled that the system enabled him to bypass the Chicago machine as an independent Democrat. “I never could have gotten elected if the party could have simply beat me one-on-one,” Mikva said. “I didn’t have a lot of money.”

According to Mikva, by targeting the 25 percent threshold that would suffice to win, “You could appeal to a much smaller set of voters. That involves a much smaller amount of money being spent on them…advertising, media, so on.”

Although cumulative voting did keep many seats outside the party bosses’ grasp, the way the rules worked could actually reinforce some patterns of strongarm politics. All the factions faced a continual tactical problem of making sure they fielded the correct, which is to say winnable, number of candidates.

For example, a political group that could capture one seat through disciplined triple voting might be left empty-handed if it ran two or three candidates who split its vote. As a result, potential spoiler candidates were predictably pressured to stay off the ballot, and parties regularly left one or two of their ballot positions unfilled, reducing voters’ effective choice.

In fact, it became common for the parties to agree informally on an uncontested two-one split that would result in no competition at all. A 1970 reform sought to ensure some modicum of competition by providing that each party had to at least nominate, if not actively support, at least two candidates.

In other words, two functions emerged as vital to cumulative voting strategy: arm-twisting political hopefuls into not behaving as spoilers, and then, should a real race emerge anyway, disciplining voters to cast the needed vote combinations. Yet political machines are actually better than loose assemblages of citizen volunteers at organizing to get these sorts of tasks done. The same is true of striking, and sticking to, informal deals with other factions. The resulting paradox is that cumulative voting may actually have strengthened the grip on Illinois of a machine politics style.

Why did voters finally ditch the system in 1980? A legislature had voted itself a big pay raise, and amid the resulting wave of popular ire advocates organized a constitutional amendment billed at cutting the number of legislators—which, incidentally, eliminated cumulative voting. It passed.

Although launched with reformist motives, Illinois’s cumulative voting system might disappoint the sort of reformer who prizes sincerity and deplores gamesmanship. On the other hand, it does seem to have excelled at including minority viewpoints, and may even have advanced some rough approximation of proportional representation, a goal some election reformers are currently eager to reach. Beyond all that, it also—like so many policy ventures—yields an object lesson in unforeseen consequences.