- Democratic candidates Hillary Clinton and Bernie Sanders will vie for support from voters in all three states. Polls reveal Clinton is poised to take Arizona easily, while the two candidates could potentially split Idaho and Utah.
- Republican candidates Donald Trump, Ted Cruz and John Kasich will only have to worry about voters in Arizona and Utah. The candidates held their primary in Idaho on 8 March, with Cruz winning with 45.4% of the vote. Trump followed in second with 28.1% and Kasich came in last with 7.4%.
- Clinton and Trump will hope to extend their leads in delegate counts. Clinton currently holds 1,163 pledged delegates, while Trump has 681. Democrats need 2,383 delegates for the nomination, while Republicans need 1,237.
- For a full breakdown of tonight's races, check out our complete guide here.
★ Winner called by The Associated Press
That's a wrap for our live coverage of the Democratic and Republican presidential primaries and caucuses. Thanks for joining and be sure to come back for continued election coverage and analysis.
The Associated Press has declared Ted Cruz the run-away winner of the Utah Republican caucus. With 24.2% of the total vote counted, Cruz racked up 70.7% to John Kasich's 16.0%. Donald Trump brings up the rear with 13.3%.
If Cruz maintains at least 50% of vote, that would hand him all 40 Utah delegates and would breath needed life back into his campaign.
Utah's support for Cruz also signals big problems for Trump in the general election if Trump ultimately wins the nomination. Recent polls have shown that residents of the state dislike Trump to such a great degree that Utah could actually go blue in November — something that hasn't happened in half a century.
Bernie Sanders trounces Hillary Clinton in the Utah caucus. Sanders was declared the winner with only 11% of the vote in, capturing 74.8% to Clinton's 24.1%.
What does Donald Trump know about Ted Cruz's wife? We may never find out.
Trump tweeted — then deleted — a message that included a threat to "spill the beans about his wife" because of a "low level" Cruz ad featuring Trump's wife, Melania.
The ad, however, didn't come from the Cruz camp, but from an anti-Trump organization seeking to rally Mormon voters, according to Buzzfeed. It featured a nude Melania Trump curled up on a fur in Trump's private jet.
"Meet Melania Trump, your next First Lady — or, you could support Ted Cruz Tuesday," says the ad, paid for by Make America Awesome that's "not authorized by any candidate or candidate committee," states a disclaimer.
The photo is from a 15-year-old photo shoot that appeared in GQ Magazine.
Trump edited his tweet slightly and reposted it — but still threatened to "spill the beans" on Cruz's wife.
Cruz's wife, Heidi, left a job at Goldman Sachs to support Ted Cruz's presidential bid. Her struggle with depression has been previously reported.
Here was Cruz's response to the Trump's Twitter threat, which he labeled #classless:
What's The Donald's big stumbling block in Utah? Mitt Romney. The respected Mormon leader has blasted Trump and endorsed Ted Cruz.
Also, intriguingly, the Mormons who dominate state politics don't care for Trump's position on Muslims. They're very aware of religious persecution in their early history in America and don't like to see anyone singled out for their faith, say analysts.
The state could be a significant victory for Cruz. If he manages to win over 50% of the vote, he'll walk away with all 40 delegates; otherwise delegates will be awarded proportionally depending on each candidate's share of the vote.
What does Trump's win in Arizona mean? Well it puts him even further ahead and one step closer to winning the Republican nomination. The state offered 58 delegates, all of which go straight to Trump. He now boasts of 739 delegates and is leagues ahead of Cruz, who has 425 delegates, Kasich, who only has 143.
If the pre-caucus polls are to be trusted, Trump won't do as well in Utah. There, the billionaire real estate mogul is in dead last, with Cruz leading the pact. There are 40 delegates up for grabs there for Republicans.
Rosario Dawson is speaking to a crowd of Sanders supporters before the candidate comes on stage. Sanders just suffered a devastating loss in Arizona. Check out the live feed here.
Despite voting still in progress in Arizona, The Associated Press has already called the race for both Clinton and Trump.
Results from Arizona are slowing beginning to come in. However, it could be hours until the full results, including the winners, are known. Sanders made sure to make his displeasure known.
Initial results show Clinton and Trump leading by wide margins.
It appears like we might be in for a long night...
GOP frontrunner Donald Trump reportedly threatened to "spill the beans" on rival Ted Cruz's wife, Heidi, after an advert aired featuring Trump's wife Melania.
The problem is that Cruz's campaign did not release the adverts, which used photos from Melania's GQ photoshoot. The adverts was actually released by anti-Trump super PAC Make America Awesome. The Instagram adverts were geared towards Mormon women.
Republican strategist Liz Mair, who runs Make America Awesome, made sure to let Trump know her super PAC was behind the adverts, while taking a dig at the bombastic real estate mogul. "Donald Trump is so desperate to beat Cruz that his team has been pushing around rumors she's a criminal w a mental illness for weeks now," she tweeted.
Cruz was quick to hit back at The Donald.
What about Idaho and Utah?
Only Democrats will caucus in Idaho, Republicans held a primary on 8 March. The caucuses began at 9pm EDT/1am GMT. There are 33 delegates available and they will be awarded proportionally. Polling in the state is scarce, but a poll in February put Sanders ahead by a mere two points, 47% to 45%.
Both parties will hold caucuses in Utah. The caucuses began at 8pm EDT/12am GMT for Democrats and 9pm EDT/1am GMT for Republicans. There are 40 delegates available to Republicans. Whoever wins a majority of the voters will receive all the delegates. Meanwhile, there are 33 delegates available to Democrats and they will be awarded proportionally.
Results from the Arizona primary, which closed the polls at 10pm EDT/2am GMT, will begin to roll in soon. There are 58 delegates up for grabs for Republicans and 75 at stake for Democrats.
Welcome to our live coverage of the races in Arizona, Idaho and Utah. We will be updating with the latest results from the primaries in Arizona and any updates from the Idaho and Utah caucuses.