There are only a few primaries left, which means presidential candidates who are trying to secure their party’s nomination are running out of time.

Following the New York primary April 19, pollsters predicted that Republican candidate Donald Trump will come close to, if not make, his party’s delegate threshold before the Republican National Convention this summer in Cleveland.

The big unknown is: What happens if he fails to make the delegate threshold?

For months, Trump’s opponents have tried to rally together to deny the frontrunner an outright victory in the primary. Their hope is to keep Trump at bay to force a brokered convention and possibly take the nomination from him.

What is a brokered convention?

The Republican Party prefers the term “open convention,” but the more traditional term is “brokered convention.”

Basically, it’s what happens when no candidate wins a majority of the delegates to clinch the nomination.

There’s another term used, “contested convention.” We’ll get to that in a moment.

First, let’s revisit how a candidate gets the nomination.

Each state holds primaries or caucuses. Depending on how many votes a candidate gets, they get a number of delegates. In some states, they get a proportion of delegates; in others, they get all of the delegates. Each candidate needs to amass a certain number of delegates to win the nomination. For Republicans, that number is 1,237 delegates.

We've delved into how the states pick delegates before, but basically, most of the states bind their delegates to the candidate who wins the primary, at least through the first round of ballots.

What is a contested convention?

In a contested convention, no candidate has amassed the 1,237 delegates before the Republican convention.

However, there are ways for a candidate to pick up delegates before the first ballot is voted on.

For one thing, while most delegates are bound to a candidate, not all of them are.

There are six states or territories with potentially unbound delegates: North Dakota, Wyoming, Colorado, Guam, American Samoa and the U.S. Virgin Islands. These delegates can vote for anyone from the beginning.

Then there’s Pennsylvania. The state has 71 delegates, but only 17 are bound to the candidate who wins the statewide primary. The state has 54 unbound delegates who will be chosen separately and will be able to vote as they wish.

How those unbound delegates decide to vote is a big question mark. All of the candidates are trying to woo these delegates. Sen. Ted Cruz is making a big play in Pennsylvania, hoping to pick up those delegates.

What happens when we get to the RNC?

In July, everyone will gather in Cleveland for the Republican National Convention. 

First, delegates will vote for their convention’s rules. These rules will be drawn up before the convention.

A majority of delegates have to approve the convention rules before candidate voting can happen.

RNC Chairman Reince Priebus has said he wants to make sure nothing in the rules will change in a way that could affect the nomination as determined by Republican voters.

Currently, a potential candidate must win a majority of delegates in 8 states to get on the first ballot. That rule should stay in place going into the convention.

Now, it is possible to suspend the rules at the convention. That would take a 2/3 majority vote from all delegates. If that happens things could get interesting.

After the rules are finalized, delegates will cast their vote for the candidate. Bound delegates will be required to vote as their state determined, while unbound candidates will be able to vote as they wish.

What happens if the convention is brokered?

If no candidate wins the nomination after that first round of ballots, the convention is considered “brokered.”

After this point, some states will release their delegates and allow them to vote as they choose. Not all states, however — Florida delegates are bound to a candidate through the first three rounds of ballots.

Once the convention becomes brokered, the nomination is open to anyone. Even candidates who suspended their campaigns during the course of the primary season could be nominated, as well as candidates who never ran in the primaries.

House Speaker Paul Ryan recently said he would not accept the nomination if offered to him in a brokered convention. Some speculate 2012 presidential nominee Mitt Romney is angling to be the GOP’s white knight candidate.

But delegates who are bound to the candidate support that candidate, right?

Now, here is where the landscape can change rapidly.

Depending on the state, delegates are not required to favor the candidate they are bound to. Only to vote for them.

Sen. Marco Rubio did not win Florida. But in April, 15 Rubio supporters were selected as delegates in Miami. Those delegates will be required to vote for Donald Trump, who won all 99 of Florida’s delegates, through three ballot rounds. After that, anything goes.

How bad could it get?

At the 1880 Republican National Convention in Chicago, the GOP when 36 rounds before delegates chose James Garfield, who wasn't a candidate, originally. (Library of Congress)


It’s been decades since we’ve had a truly brokered convention. In 1952, Dwight D. Eisenhower won the Republican nomination on the first ballot, but only after delegates for another candidate broke away at the last minute.

In 1880, Republicans went through 36 rounds of ballots before delegates compromised. They chose James Garfield, a senator from Ohio, to be the party’s nominee. Garfield was not even one of the candidates up for election. He was the campaign manager for another candidate.

Garfield ended up being assassinated, dying only 200 days into his first term.

Even the first Republican National Convention was brokered. Abraham Lincoln secured the nomination after three ballot rounds in 1860.

The record for a brokered convention, however, falls to the Democrats.

The 1924 Democratic National Convention dragged on for weeks, through 103 ballots. Democrats eventually elected John Davis as the nominee.

However, Democrats have put a mechanism in place (superdelegates) to help make sure they do not have a contested convention.