When Maine voters head to the polls for June 12 primary elections, the way they vote will be drastically different.

Maine is the first state in the nation to use a ranked-choice voting system in both the congressional and statewide primary elections Tuesday.

On the ballot, too, is whether voters want to continue to use ranked-voting in the future, with a ballot initiative that seeks to use ranked-choice for U.S. House and Senate races in November. The system has gotten the backing of actress Jennifer Lawrence who, in an online video, encouraged Maine voters to “protect ranked-choice and our democracy.” Lawrence has said she’s taking a year off of acting to work with an advocacy organization to “fix our democracy,” starting with state-level issues.

Sometimes also called an instant runoff, the system is already used in 11 local jurisdictions nationwide.

How this system works

Under this system, voters rank candidates on the ballot in order of preference -- instead of just choosing one person, according to a fact sheet from the Maine secretary of state’s office. If a candidate wins the majority of the vote, then they are declared the winner.

However, if no candidate receives a majority, then votes are counted in rounds with the lowest-ranked candidate eliminated per round until only two remain in a mathematical game of survival. For example, once a candidate is eliminated, the second-choice picks for voters who chose that eliminated candidate will then be counted as the remaining contenders move on to the next round. This process continues until only two candidates remain, with one receiving the majority of the vote. That person will be declared the winner.

That means the eventual winner might not be the candidate who had the most first-place votes to begin with but rather the one who tallies the highest number of second- or even third-place votes.

According to the secretary of state’s office, voters are able to just select their first-choice candidate. But voters who select more than one candidate as their first choice will have their ballots invalidated.

Voters are also unable to select a candidate as their first, second and third choice. Only the first choice vote will be tabulated.

Ranked-choice voting can only occur if there are at least three candidates on the ballot.

Only four races will use ranked-choice voting

There are only four races where voters will use the ranked-choice system as there are more than two candidates in those races, according to the Maine secretary of state's office.

Those races are: both Republican and Democratic nominations for governor, Democratic nomination for U.S. representative in the 2nd congressional district and the Republican nomination for the state legislature in House District 75.

Don’t expect to know the winners immediately

According the Bangor Daily News, Maine voters shouldn’t expected to know the first-round winners in all races immediately on election night because the state needs additional time to be able to retabulate the ranked-choice races.

For example, there are seven Democrats and four Republicans running in the respective gubernatorial primaries. And with a field that large, it’s unlikely one candidate will walk away with the majority in the first round, the Daily News reported.

Ballots will be brought to Augusta for tallying by couriers hired by the state, according to the newspaper.

New campaign strategies

The ranked-choice voting system has set off a new campaign strategy for two Democrats vying for the gubernatorial nomination.

Democrats Mark Eves and Betsy Sweet, both vying for governor, appeared in a campaign video together where they gushed about each other’s credentials and encouraged voters to select them both.

“So on June 12, you can vote for me first and Betsy second,” Eves said with Sweet next to him.

“Or, me first and him second,” Sweet said.

Advocates of the system have pointed to this type of campaign style, saying it promotes civility in politics.

Not everyone likes it

Moving toward a ranked-choice voting system started as a bipartisan effort, but it has since become highly politicized with Republicans attempting to stop or delaying it in court.

In May, the Maine Republican Party filed a federal lawsuit to block the ranked-choice voting system from taking effect, the Portland Press-Herald reported. But by the end of the month, a federal judge denied the GOP’s request for a preliminary injunction stopping the process ahead of the primary election.

Some voters, such as Kent Long who already turned in an absentee ballot, have said they still plan to only vote for one person.

“We vote for whom we think is best,” Long told The Associated Press.

Fox News’ Molly Line and The Associated Press contributed to this report.