DONALD Trump is facing a tough challenge in Utah's caucuses, but the Republican US presidential front-runner could still gain some delegates if sharp party divisions prevent anyone from winning a majority in the conservative state that prizes civility and religion.
For the Democrats, Hillary Clinton is likely to extend her overwhelming delegate lead over rival Bernie Sanders in contests in Arizona, Utah and Idaho, moving closer to becoming the first woman presidential nominee from a major political party.
The former US secretary of state and first lady now has 1,163 delegates to Mr Sanders's 844, based on primaries and caucuses. It takes 2,383 delegates to win the nomination.
Mr Trump's remaining rivals, Texas senator Ted Cruz and Ohio governor John Kasich, were also fighting in Arizona on Tuesday to stop the New York billionaire from building an insurmountable delegate lead.
Both Mr Cruz and Mr Kasich want to keep Mr Trump from gaining the required 1,237 delegates to win the Republican nomination, ultimately forcing a contested convention to take place in July.
Mr Cruz is likely to do well in Utah. He has been helped by the support of Mitt Romney, the Republicans' most recent presidential nominee, who holds clout among the state's predominantly Mormon voters. The Texas senator also picked up the endorsement of Utah governor Gary Herbert on Monday.
But Mr Kasich was fighting back in Utah, hoping his more pragmatic approach and long-time governing experience will net him delegates there.
According to Utah state regulations, if no candidate wins more than half of the caucus votes, each of the three candidates will be awarded delegates proportionally. The candidate who can win Utah by more than 50 per cent will walk away with all 40 delegates.
Mr Trump could significantly benefit from those rules if Mr Cruz does not win the majority. The former reality television star goes into Tuesday's contests with 680 delegates in hand. Mr Cruz has 424 and Mr Kasich has 143.
On Monday, Utah Republicans received a pre-recorded call from Mr Romney urging them to back Mr Cruz, not Mr Kasich. "At this point," Mr Romney said on the call, "a vote for John Kasich is a vote for Donald Trump."
Mr Cruz, a fiery conservative, often lashes out against Republican establishment figures, many of whom traditionally thrive in Utah. But leaders like Mr Romney and Mr Herbert have consolidated around Mr Cruz because he is seen as the only one who can catch up Mr Trump's delegate lead.
Mr Trump appears to be in a stronger position in Arizona, which will award all of its 58 delegates to whichever candidate wins the most votes.
There is a widening divide among Republicans nationwide. A total of all the votes cast thus far shows that a majority of Republicans have chosen someone other than Mr Trump, but he has managed to amass a majority of delegates.
