With the Democratic and Republican national conventions behind us, the big news seems to be the surge in support for third-party candidates, rather than for Hillary Clinton or Donald Trump, our two major presidential nominees. Recent national polls, including the latest from The Economist and YouGov, show the Libertarian nominee Gary Johnson up to 8 percent of support and Green Party nominee Jill Stein at 4 percent. This has the potential to disrupt the race, even in favor of Trump. With that in mind, there are nine arguments against voting third-party that put the election into a larger context.

Those aforementioned percentages are relatively big compared to how both candidates fared when they ran in 2012. In September 2012, polls put Johnson at 3 percent and Stein at 1 percent, according to Real Clear Politics. That's significantly lower than what we're seeing now. Even if the polls don't match actual votes come November, the rise is still notable. In the end, Johnson took home just one percent of the vote in 2012 and Stein 0.36 percent, so we can expect some drop in their support before Election Day.

But perhaps even more notable is the third-party support among voters under 30. A combined 30 percent plan to vote for Johnson, Stein, or someone else, according to the The Economist/YouGov polls. That means that nearly a third of your friends (or maybe you) are planning on voting this way. Supporting a candidate like Stein or even Johnson is not necessarily a bad thing, but here's why you might want to reconsider, or convince your friends to — especially when 62 percent prefer Clinton to Trump.

1. We Don't Have A Parliament

We don't have a parliamentary system or runoff round of voting for president. In countries like the United Kingdom, many parties make it into Parliament. Then the first-place winner tries to form a coalition government if they don't have more than half the seats. So even if your party doesn't come in first, they still get a say.

Another setup, like what they use in Brazil, is a runoff system. If no candidate receives more than 50 percent of the vote, then the top two finishers run against each other. That way, voters who didn't vote for the top two still get a say in the final decision. The United States doesn't have this.

So unlike Brazil, where you get to vote again if the vote is close, you just get one shot here. The same goes for the parliamentary system, where your party choice could still be part of a coalition. When your third-party candidate loses here, that's that.

2. Blame The Electoral College

Instead, we have the Electoral College system. This is actually what puts someone in the White House — not the popular vote. I'm not here to sing its praises, but this is currently how it works. Each state gets votes based on how many Senators and Representatives it has in Washington, D.C. Then D.C. gets a proportional amount that's equivalent to no more than those in the smallest state (so three).

Almost all of these states and D.C. decide who gets their Electoral College votes based on who gets the most votes there. It's not proportional to the popular vote. It's purely winner-take-all. So even if a third of the country voted for a third-party candidate, that might not translate into much of a win in the Electoral College because of another candidate coming out ahead in each individual state election.

3. Duverger’s Law

A French political scientist called Maurice Duverger tried to explain why we only have two dominant parties in our political system. It's the way the system is made, and not just at the presidential level. Take the House and Senate as an example, as there is just one member that you vote on at a time to represent you. Then the winner is decided by whoever receives the most votes. There is no runoff election. The Washington Post explained what that means:

That winner-takes-all nature of single-member districts encourages broad coalitions to form before elections. The odds of a party winning such elections are much higher if only two parties exist, enabling each side to work to bring as many people to its side as possible.

4. Florida In 2000 Is A Great Example

There are examples of what can happen when this complicated, arguably messed-up system is put into play in the real world. One of those would be the Florida in 2000. Forget whether all the votes were counted, or whether George Bush stole the election. Bush was ahead by just 537 votes when the election was called. That was the official margin, regardless of all the actual and potential recounts. Guess how many people voted for the other progressive candidate in Florida that year? The Greens' candidate Ralph Nader took home more than 97,000 votes. Historians argue it won Bush the election, as do pollsters.

5. Bernie Sanders Said Not To

If you're a fan of Bernie Sanders, it's important to note that he sees a Clinton presidency as the best way forward for the country. Not only did he endorse her, but he also shut down third-party hecklers at a breakfast during the DNC:

I don't know the leadership of the Green Party, but I respect what they're trying to do. They're focusing on very, very important issues. But I think right now — what is it, three, four months before an election — you're going to end up having a choice. Either Hillary Clinton is going to become president, or Donald Trump.

6. Sanders' Primary Made The Third-Party Point

Given that the Greens likely won't win, the main point of voting for them would be to show that there are Americans who believe in progressive policies like universal healthcare, free post-secondary education, and a living wage, among other things. It could show Democrats there are enough people supporting those policies that they should be included in the Democratic platform. But that already happened thanks to Sanders' participation in the primary. Sanders ran far to the left of Clinton, and in doing so, he pushed her to the left, too. And the Democrat's party platform was changed as a result. Sanders delegates passed many of his key positions as planks.

7. Trump And Clinton Are Not The Same

One of the big arguments right now among third-party supporters is that Trump and Clinton are both bad, and that we shouldn't have to choose the least evil candidate. I would argue that Clinton is not evil, nor a bad candidate. Is she perfect? No, she is pragmatic and often compromises. But that's not necessarily a bad thing. Also, she has a long history in public service, both in and out of government. Her experience as both a senator and secretary of state make her the most experienced and qualified candidate ever, as Obama pointed out at the DNC.

8. The Moral Argument

Another argument that has made the rounds is that the moral choice is to vote for Stein, because she wouldn't continue the current U.S. policy in the Middle East, particularly drone warfare. Thus, if you vote for Clinton, you're responsible for every policy that she carries out. But as Matthew Rozsa, a Ph.D student, explained on Salon, the moral thing to do is to vote for Clinton.

Because the election will ultimately come down to Trump and Clinton, the way to frame your vote is around the people whom you're helping or hurting. With Clinton, you'd help people in need of immigration reform. The 11 million people without legal citizenship documentation would be at risk of being rounded up under Trump. Additionally, Clinton has proposed an infrastructure improvement plan that would provide the largest number of new jobs since the New Deal. Trump would actually hurt people, Rozsa argued. Particularly through racism — not to mention possible nuclear war if he controlled the launch codes.

9. Maybe Don't Start With The Presidency

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There could be many benefits to a multi-party system forming in the United States, and that's a real possibility in the future. But it might make the most sense to start at the local and state level. Already, there are places where third-party candidates do better in presidential elections, as The Atlantic showed. It's basically anywhere that is firmly Democrat or firmly Republican.

California is a good example, as third-party candidates tend to do well there. For example, their research showed that Nader took home 3.82 percent of the vote there in 2000, compared with just 1.63 percent in swing state Florida. If you look at the Green Party in California, they won 14 of 17 races they ran in 2015, and 34 of 58 in 2014. Statewide, they hold 70 public offices.

This could be the perfect place to build up a third party. Already, the Republican Party is suffering in the state. Then voters passed Prop 14, which allowed for a top-two primary for statewide and Congressional offices. The top two candidates in the primary of any party make it to the general. That means that if a Green Party candidate gets the second-most votes, they would appear on the ballot, not a Republican. This year, we've seen it play out with the Senate race, as two Democrats (both women) will appear on the ballot in November.

But it doesn't have to be two Democrats. And this is one of the alternative forms of voting that could reduce the two-party dominance. Try to change voting at your local or state level to support third-party candidates, and then elect them. You don't have to use your vote for president to change the system. Start from the ground up, and build a foundation that can be used to elect candidates successfully on the national stage.