The American electoral system is not always the same in every state, as states like Maine are using methods like ranked choice voting.

Ranked-choice voting refers to the system where voters rank candidates by preference on their ballots. The candidate who secures the majority of first-rank votes wins in this system. Meanwhile, approval voting is a single-winner voting method that allows voters to choose any number of candidates. The candidate with the most selections wins.

Aaron Hamlin, the Center for Election Science‘s executive director, spoke to uPolitics exclusively at the 2019 Netroots Nation political convention for progressives in Philadelphia. Hamlin explained why the approval voting system is more practical than the ranked choice one. The CES is a national nonpartisan nonprofit that aims to help implement more efficient voting methods.

Given the high number of Democratic candidates running against President Donald Trump in the 2020 presidential election, the different types of voting system used in different states will likely be discussed at some point.

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“[Approval voting addresses a number of issues,” said Hamlin. “You don’t have to worry about vote-splitting: if there are multiple candidates that you like, choose multiple candidates. You don’t have to worry about betraying your favorite [candidate,] you can always support your honest favorite. If you want to have a say in the outcome, support one of the front-runners as well. This method also tends to elect a more consensus-style winner.”

Hamlin cited some of the “logistical issues” caused by ranked-choice voting. He also noted that Fargo, North Dakota, is an example of a city that implemented an approval voting system last year, and said the CES is pushing to introduce this system to St. Louis, Missouri in 2020.

“To change St. Louis’s voting machines would cost millions of dollars, whereas approval voting is a method that’s shovel-ready, you don’t need any kind of special software, you just go ahead an implement it,” Hamlin said before adding that approval voting gives independents and third-party candidates a “much more accurate reflection of support.”

Hamlin said the CES is also working on publishing a study about the 2016 election and four different voting methods that were used for it: approval voting, ranked-choice voting, score voting and the most widely used system, single-candidate voting.