Leading Democratic and Republican contenders have split major wins in presidential nominating contests in Arizona and Utah.
Donald Trump rolled to a victory in the Arizona Republican primary, capitalising on his anti-immigration stance - a position that has long been popular with conservative voters in the state. With the win on Tuesday, Trump takes all of the state's 58 delegates to the Republican National Convention.
In the Democratic Arizona primary, Hillary Clinton was projected to easily account for Vermont Senator Bernie Sanders.
But Sanders flipped the script by beating the former secretary of state in the Utah caucuses. He doubled up by also taking the Idaho caucuses on Tuesday.
Trump won more than 45 percent of the vote in Arizona, compared with about 21 percent for his main rival, Texas Senator Ted Cruz.
The billionaire businessman made three trips to Arizona and had the support of Maricopa County Sheriff Joe Arpaio and former Governor Jan Brewer - a pair of politicians best known for leading immigration crackdowns.
However, Cruz - like Sanders - looked like countering his party's frontrunner by winning Tuesday's Utah caucuses.
Early in the count, Cruz was leading with nearly 70 percent of the vote. By winning more than 50 percent, he will carry all of the state's 40 delegates.
And in a further boost for the Texas senator, former Florida Governor Jeb Bush announced on Wednesday that he was endorsing Cruz for president.
Bush, who dropped out of the race in February, said Cruz was a "consistent" and "principled" candidate.
Clinton padded her delegate lead with her win in Arizona.
With 75 delegates at stake, Arizona is the biggest prize of the night in the Democratic race.
Clinton stands to gain more than half of those delegates - at least 40, compared with at least 16 for rival Bernie Sanders. That means she will add to her delegate lead of more than 300. She now has 1,203 to Sanders' 860.
By winning the Utah and Idaho caucuses with about 75 percent of the vote, however, Sanders will not suffer too much in the overall count.
|Presidential candidate Bernie Sanders holds a campaign rally in San Diego, California on Tuesday [Mike Blake/Reuters]
Source: Al Jazeera and agencies