The front-runners for the Democratic and Republican presidential nomination split contests with their chief rivals Tuesday in a set of western states.

Republican Donald Trump easily won Arizona and all of its 58 delegates, defeating Texas Senator Ted Cruz by more than 20 percent.

Cruz bounced back with his own resounding win in Utah. He got more than half the vote, qualifying him for all of Utah's 40 delegates and denying Trump any portion of that total. Cruz and the other remaining Republican candidate, Ohio Governor John Kasich, are trying to keep Trump from gaining the 1,237 delegates needed to clinch the party's nomination before its convention in July.

That difference is big as Cruz tries to deny every possible delegate to Trump to keep him below the 1,237 needed to clinch the Republican nomination.

Vermont Senator Bernie Sanders scored two much-needed routs in the Democratic race, winning caucuses in both Idaho and Utah with more than 70 percent of the vote over former Secretary of State Hillary Clinton.

Democrats award their delegates proportionately, so Sanders has to earn lopsided victories in order to close Clinton's overall lead. She won the Democratic contest Tuesday in Arizona by a wide margin.

Tuesday’s voting took place in the hours after the deadly terrorist attacks at the airport in the Belgian capital of Brussels and at a subway station not far from the European Union headquarters.

Trump, who called for a temporary ban on Muslims entering the U.S. after previous attacks linked to Islamic terrorists, said he had warned about new assaults. “Brussels was a beautiful city, a beautiful place with zero crime, and now it’s a disaster city,” Trump said.

Kasich said the global community must “redouble” its efforts to “identify, root out and destroy the perpetrators of such acts of evil.” Cruz declared that “radical Islam is at war with us,” and said that if he is elected president, he would unleash the “full force and fury” of the U.S. military to defeat Islamic State jihadists.

Clinton said the U.S. must “stand in solidarity” with European allies in fighting terrorism. “We’ve got to be absolutely strong and smart and steady in how we respond,” she said. Sanders declared, “This type of barbarism cannot be allowed to continue," saying the attack was a “brutal reminder that the international community must come together to destroy” Islamic State.

The Republican contest in Utah is a microcosm of the efforts by Cruz and Kasich to keep Trump from moving closer to the 1,237 Republican convention delegates he needs to clinch the presidential nomination before the quadrennial gathering convenes. His opponents want to keep him under that threshold and instead throw the convention to an open vote.

The party’s 2012 nominee, Mitt Romney, said he is voting for Cruz on Tuesday and urged others to do the same, calling supporting Cruz the only way to get to the open convention and stop Trump. Last week, Romney endorsed John Kasich before the Ohio governor won the winner-take-all primary in his home state, thus denying Trump a big haul of delegates in the midwestern state.

After Tuesday, Republicans have just two contests over the next three weeks, in the midwestern state of Wisconsin on April 5 and in the western state of Colorado on April 9. (VOA)

•Photo shows Democratic presidential candidate, Sen. Bernie Sanders, I-Vt., arriving at the San Diego Convention center for a rally Tuesday, March 22, 2016.

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