- Written by Jude Sheerin
- BBC News, Washington
WATCH: Why this Super Tuesday isn't as fun as previous ones
Super Tuesday, the biggest day of the 2024 White House campaign so far, is approaching.
On March 5, voters in 15 states and one U.S. territory will choose their presidential candidates.
As Joe Biden and Donald Trump hurtle toward a rematch in November's general election, we're sure to get a glimpse of their strengths and potential weaknesses.
What is Super Tuesday?
This is the time when most states vote on their presidential primary dates.
Nominating contests include Alabama, Alaska, Arkansas, California, Colorado, Maine, Massachusetts, Minnesota, North Carolina, Oklahoma, Tennessee, Texas, Utah, Vermont, Virginia, and the United States. It will be held in Territory Samoa.
Republican races will be held in all 15 states, while Democrats will vote in the same states except Alaska. The party also plans to hold a caucus in American Samoa.
Results from the Democratic race in Iowa, which have been in the mail for several weeks, are also expected to arrive.
How many delegates are selected as candidates?
Based on the results of each contest, party officials called delegates are awarded to the top candidates. Each party will need a certain number of delegates to formally appoint candidates at their conventions this summer.
About a third of the delegates (865 Republicans and at least 1,420 Democrats) are in contention on Super Tuesday.
Trump's campaign expects him to win at least 773 delegates that day and clinch the nomination in late March. He now has an estimated 244 delegates, compared to 43 for his Republican rival Nikki Haley.
Republicans need at least 1,215 delegates to win the nomination, but 1,968 is the magic number for Democrats.
Learn more about US elections
What's at stake for Trump?
The Republican front-runner, who is trailing by double digits in opinion polls, will be hoping to knock his last remaining rival out of the race.
Haley, a former U.N. special envoy, has so far received only one of about a dozen nomination votes and is still in the running even as deep-pocketed donors close their wallets.
She has no clear path to victory, but Super Tuesday could be her last chance to disrupt Trump's momentum or expose his potential vulnerabilities ahead of the general election.
In previous elections, Mr. Trump has struggled to gain support from college-educated suburbanites, a demographic that could ultimately thwart his dreams of returning to the White House.
What about Biden?
The Democratic president is all but certain to win his party's nomination, despite long-term challenges from Congressman Dean Phillips and self-help author Marianne Williamson.
On February 27, during a registration drive to protest the president's support for Israel in Michigan, the Biden campaign stumbled as 13% of voters declared themselves “uncommitted.”
A last-minute campaign is being put together to have similar protest votes held in other states on Super Tuesday. California, Colorado, North Carolina, Minnesota, and Vermont are among the states with such efforts underway.
More broadly, national exit poll data could reveal whether disparities in enthusiasm among key blocs, including younger voters, pose a challenge to his re-election.
When will I know the results?
Voting will take place in six time zones, so the final results won't be immediately known.
Results will begin trickling in once voting closes in the evening on the East Coast.
US networks, including the BBC's US partner CBS News, are expected to begin calling states from around 20:00 ET (01:00 GMT).
What other contests should we look out for?
All eyes will be on North Carolina, the only battleground state in the general election where voting will take place on Tuesday. Mr. Trump beat Mr. Biden in this area in 2020 by just over 1 percentage point.
Following the Supreme Court's ruling, Trump remains on the ballot in Colorado and Maine, even though both states seek to disqualify him on suspicion of inciting insurrection.
A potential wildcard is that some states are completely open to voters regardless of party registration. One is Virginia, where Republican voters have a relatively moderate reputation.
Old Dominion State may be Haley's best hope of solace in what is expected to be a tough night for her.
