What are delegates?

How many delegates does a candidate need to win?

What's a superdelegate?

Who are the Democratic superdelegates this year?

What happens to Marco Rubio's delegates?

Hillary Clinton is just a few dozen delegates away from securing the 2,383 commitments she needs to win the Democratic nomination . On the Republican side, Donald Trump crossed that threshold in May. Ahead, we break down what a delegate actually is and how the system works.This story was originally published on April 14, 2016.Now that many of the state primaries and caucuses are over, what's next for the presidential candidates this election season? It's all about delegate math — how primary and caucus results are converted into delegates who actually pick a candidate at this summer's Republican and Democratic party conventions. And on the Democratic side, it's not just the delegates — there are also superdelegates to worry about.Here's how the delegate system really works, with breakdowns of how many delegates the candidates will need to win their parties' nominations.Delegates attend the Republican and Democratic national conventions on behalf of the candidates they're pledged to, based on the results of the caucuses and primaries that have taken place so far. For the 2016 presidential election, there are 2,472 Republican delegates at stake and 4,763 for the Democrats.The way the two parties award their delegates is different: All of the Democratic delegates are awarded proportionally, rather than in a winner-take-all situation. But among Republicans, the process varies from state to state.To capture the Republican primary nomination, a candidate will need 1,237 delegates; on the Democratic side, the magic number is 2,382. Those figures represent the point at which a candidate has earned the votes of 50% of her or his party's delegates.Donald Trump currently has 743 delegates, while Ted Cruz has 545, according to The Wall Street Journal . On the Democratic side, Hillary Clinton has 1,289 pledged delegates, while Bernie Sanders has 1,038.The Democratic race differs from the Republican process in one major way: superdelegates. Of the 4,763 Democratic delegates, 712 — about 15% — are superdelegates. These are delegates who go into the Democratic convention unfettered to any specific candidate, unlike so-called pledged delegates. In other words, they're free agents — and they hold lots of power.Superdelegates include elected officials, i.e., senators and members of the House of Representatives; certain members of the Democratic National Committee; and notable Democrats, such as current and former presidents and vice presidents, CBS News explains . They are, in many cases, literally elder statesmen and women who can be expected to represent their party's core values when pledging their votes.As of April 9, 469 of the Democratic superdelegates had expressed support for Hillary Clinton.As the AP notes , Republicans do have superdelegates, but the process is less of a "wild card" situation. At the 2012 Republican National Convention, the party implemented a rule that delegates must be awarded to candidates based on caucus and primary results. The rule affects most of the 168 RNC members who would previously have been free agents at the convention. But superdelegates from Colorado and North Dakota aren't pledged to any candidate, since those states don't actually hold votes in their Republican caucuses.President Obama and Vice President Biden, as well as former President Bill Clinton, former Vice President Al Gore, and former Vice President Walter Mondale, are superdelegates for the 2016 Democratic national convention, CBS News notes. Former Sen. Chris Dodd and Virginia Gov. Terry McAuliffe are also superdelegates, since they're both former DNC chairs. Bernie Sanders himself is a superdelegate this year, since he's a Senator who attends Democratic caucuses, even though he's registered as an independent.In close races, superdelegates can influence the nomination — they make up a significant portion of the Democratic delegates. There are still plenty of primaries and caucuses before the Democratic national convention, though, so it remains to be seen just how influential they'll be this year.Florida Sen. Marco Rubio (R) suspended his presidential campaign on March 15 , after some states had already held primaries and caucuses. Rubio won 172 delegates before dropping out of the race, according to NBC News . And if he has any say in the matter, he wants to keep those delegates from supporting GOP front-runner Donald Trump.Delegate allocations are decided by each state's Republican party, though, not by the Republican National Committee, so it's up to each of the 21 states and territories where Rubio won delegates to decide how to handle the situation.NBC News explains that while in this situation many delegates are "free to support the candidate of their own choosing," Rubio has written to state parties asking that delegates remain bound to him.This post has been updated to reflect the latest state of the presidential race. It was originally published on March 3, 2016.