Washington — The Super Tuesday elections had the largest number of delegates up for grabs on a single day in the 2024 Republican presidential primary, and former President Donald Trump, the GOP frontrunner, walked away with most of them after voting ended in the 15 states holding GOP contests.

There were 865 Republican delegates at stake in the Super Tuesday states. CBS News projects that Trump will win all but one of the primaries and caucuses held and secure an estimated 777 delegates. Former U.S. Ambassador to the United Nations Nikki Haley's performance yielded her 44 delegates and one victory — in Vermont's GOP primary — though she is set to suspend her bid for the GOP presidential nomination. 

The outcome of the elections eases Trump's path for the Republican presidential nomination and with Haley's exit, sets the November general election up to be a rematch of the 2020 race for the White House between Trump and Mr. Biden. The president swept all 15 states where Democratic voters made their voices heard.

Republican delegate count for 2024 so far

Trump came into Super Tuesday day with a substantial lead over Haley in the delegate race, according to the CBS News Delegate Tracker. But the outcomes of the elections in states voting Tuesday brought a significant increase in the estimated number of delegates awarded to Trump. 

How many Republican delegates does Trump need to win the nomination?

Trump needs to win 1,215 GOP delegates to secure the party's presidential nomination and move on to the general election match-up against President Biden. 

There were 865 GOP delegates available across the 15 states that held their contests on Super Tuesday.

What are delegates?

Delegates are selected to represent their state or area at the nominating convention, and each party's delegates choose their respective presidential nominees during the gatherings slated for the summer. For Republicans, that convention will take place in Milwaukee, Wisconsin, and kicks off July 15.

In addition to voting for the candidate who will represent the party at the top of the ticket in November, delegates also approve the party platform and rules. 

The Republican Party has two types of delegates: bound and unbound. Those who are bound are required to vote at the convention in accordance with the outcome of their state's primary or caucus for at least the first round of voting, according to the Republican Party rules.

Delegates from Guam, Montana, New Mexico and South Dakota will head to the convention unbound, according to a memo from the party on the nominating process.

Why are delegates important?

The candidate who wins a state's primary or caucus is awarded delegates. Trump and Haley were each running to secure at least 1,215 out of the 2,429 at stake from all 50 states, the District of Columbia and U.S. territories to secure the presidential nomination.

Those nearly 2,500 delegates will convene at the Republican National Convention to select their nominee for president. 

How are delegates awarded?

The rules for how delegates are allotted differ for the Republican and Democratic parties. For many states on the Democratic side, delegates are allocated proportionally for each candidate who surpasses a set threshold. The allocation formulas differ by state.

The GOP rules require states that hold their elections before March 15 to allocate their delegates on a proportional basis. Only after March 15 can a state award its delegates in a winner-take-all manner.

Other states use a combination of the two methods. In some states, delegates are awarded proportionally unless a candidate wins at least 50% of the statewide vote, in which case the candidate is awarded all of the delegates.

Melissa Quinn

Melissa Quinn is a politics reporter for CBSNews.com. She has written for outlets including the Washington Examiner, Daily Signal and Alexandria Times. Melissa covers U.S. politics, with a focus on the Supreme Court and federal courts.

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