Yet another thing journalists have to explain to voters during an already complex election season: In America, some people have the voting power of 10,000 ordinary citizens.

Case in point: The Iowa Democratic caucuses ended in a virtual tie between Hillary Clinton and Vermont Sen. Bernie Sanders. But when networks reported the returns, they didn't mention the existence of a second class of voters, one that tipped the scales in Clinton's favor.

The cause? Superdelegates, highly placed politicians and influencers who get to represent their states however they wish at the Democratic National Convention this summer. Each wields voting power roughly equal to 10,000 regular votes, and their support goes a long way toward helping their candidate capture the 2,382 delegates required to win the Democratic nomination. The Republican primary system doesn't include superdelegates.

in Iowa, many superdelegates lined up behind Clinton, and she came out of the caucuses with six more delegates than Sanders. Sanders won big in New Hampshire, but the delegate count came out as a tie. So far, Clinton has barely won one state, lost a second and is still ahead of Sanders in the delegate count.

NBC News explained on Wednesday how superdelegates swung the New Hampshire vote Clinton's way:

At the end of the New Hampshire tally Tuesday night, Sanders had amassed enough support from voters to earn 15 delegates, while Clinton grabbed just eight based on the ballot box.

But New Hampshire also has eight superdelegates. Six of them have endorsed Clinton, while two aren't committed to either candidate. That means that Clinton tacked an extra six delegates on to the end.

There are 712 superdelegates. Twenty are governors, 47 are members of the U.S. Senate, 193 come from Congress and the rest are from the Democratic National Committee. Hundreds have already endorsed Clinton. So even in states that have not voted yet, Clinton has locked up lots of delegates.

An Associated Press survey of superdelegates conducted in November found that 359 superdelegates planned to support Clinton, with an additional 210 undecided. Just eight planned to support Sanders. Wikipedia users maintain an exhaustively footnoted list that puts the current tally at 415 in favor of Clinton, with an additional 14 supporting Sanders.

Nevada Sen. Harry Reid, speaking to NBC's Andrea Mitchell Thursday, said that the Democratic superdelegate system was born from a desire to establish a counterweight to the popular vote in the states of Iowa and New Hampshire.

The process was totally unfair before — eight years ago. Eight years ago, I looked at this and I thought, how in the world could we have the future of this country be dependent on Iowa, which is 93% white, and we have New Hampshire which is 97% white, no diversity, no diversity in Iowa. And have the final decision made as to who is going to be the president of the United States based on those two states, it was wrong.

The result? The superdelegate system is so tilted toward Clinton that it's exceptionally difficult for Sanders to have a shot at a nomination.

This could change, however, if Sanders picks up momentum. As the New Republic points out, superdelegates are "free to vote for their preferred nominee." So if Clinton's campaign suffered a big setback, her superdelegates could jump to a competing candidate:

The superdelegates are free to vote for their preferred nominee, unbound by the will of the voters — and if a nominee they think is terrible for the party is close to securing the nomination, they can conceivably throw their weight behind an alternative.

Under this scenario, Sanders could arrive at the national convention with the majority of popular vote and prompt superdelegates to change their allegiances rather than go against the voters' will, according to RawStory's Joshua Holland.

Perhaps comedian Larry Wilmore put the situation best when he explained the system to his viewers on "The Nightly Show."