Tampa: Donald Trump could take a giant step on Tuesday toward securing the Republican presidential nomination if he wins the Florida and Ohio primaries, which would intensify pressure for rivals from the party establishment to step down from the race.
Trump has the potential to sweep five big states holding primaries for the November 8 election - Florida, Ohio, Illinois, North Carolina and Missouri. He could knock out his two mainstream rivals, Ohio Governor John Kasich and US Senator Marco Rubio of Florida, if he wins their states.
The New York real estate tycoon has a significant lead over Rubio in opinion polls in Florida, but is neck and neck with Kasich in Ohio. Any win by either Rubio, Kasich or US Senator Ted Cruz of Texas would give at least a small degree of hope to Republicans battling to deny Trump the nomination.
Trump said on Tuesday that his momentum was already drawing in establishment Republicans who had previously balked at his candidacy but now see him as the likely nominee.
"They're already calling," he told NBC's "Today" program, without naming names. "The biggest people in the party are calling."
Trump victories in the five states could make what once seemed inconceivable a strong probability, putting the 69-year-old New York real estate mogul who has vowed to deport 11 million illegal immigrants and impose some protectionist trade policies, on a glide path to representing the Republican Party in the November election.
Trump drew first blood on Tuesday, winning the Northern Mariana Islands caucuses with almost 73 percent of the vote, local Republican Party executive director Jason Osborne said. The win in the U.S. Pacific commonwealth gives him nine delegates.
On the Democratic side, former Secretary of State Hillary Clinton can put some distance between herself and rival Bernie Sanders, a U.S. senator from Vermont, in Tuesday's voting.
Opinion polls gave her a big lead in Florida and North Carolina, but showed Sanders gaining ground in Ohio, Illinois and Missouri, a possibly worrisome sign for Clinton after Sanders' surprise victory in Michigan a week ago.
"I voted for Bernie because I want to see a real change to how we do things in this country," Jackie Zydeck, 52, an attorney for the federal government, said after voting in Chicago's liberal Albany Park neighborhood.
"I like his single-payer healthcare idea; I like his ideas about taxes," Zydeck said.
Trump held rallies in Florida, Ohio and North Carolina on Monday and said establishment Republicans who have labored to stop his outsider candidacy needed to rally to his cause.
An outbreak of clashes between Trump supporters and protesters that forced him to cancel a rally in Chicago on Friday, and scattered protests at some of his campaign events this week have prompted more concerns from mainstream party figures.
Their only real hope for stopping Trump is to deny him the 1,237 delegates needed for the nomination and extend the battle to the party's nominating convention in July in Cleveland.
"I believe the ideal outcome in this campaign is to have someone not named Donald Trump coalesce the party with 1,237 delegates and go on to defeat Hillary Clinton in November," Rubio told Fox News. "If he's the nominee he is not going to be able to unite the party. In fact I think he'll bitterly divide it."
Kasich reminded Ohio voters of Trump's confrontational campaign tactics during a final swing through his home state.
"Think of the images that have been broadcast across this world about how we are picking a president here," Kasich said on Monday, adding that the footage of protests and violence could be used to fuel propaganda that America was "broken."