Tuesday appears to be the best and last chance for Donald Trump's rivals to stop him from winning a presidential nomination.
With more than 350 delegates up for grabs in five primary states, the Republican lead is looking to score big wins that could make his march to the nomination almost unstoppable.
Trump victories in Ohio and Florida alone would most likely put him hundreds of delegates ahead of his closest competitor, Sen. Ted Cruz of Texas. Of the states voting Tuesday - Ohio, Florida, North Carolina, Missouri, and Illinois - Trump led in recent public polls in all of them except Ohio.
Most of the attention is focused on Ohio and Florida, two states where the candidate who gets the largest share of the vote wins all of the state's delegates. The states also provide do-or-die contests for two of Trump's rivals, Gov. John Kasich of Ohio and Sen. Marco Rubio of Florida, each of whom would have a hard time pressing forward without winning his home state.
Barring a massive upset, Trump appears poised to win Florida and sweep up its 99 delegates. In the RealClearPolitics average of recent polls, Trump held a massive 19-point lead over Rubio.
A Florida win would put Trump at 559 delegates, almost half the number of delegates needed to secure the Republican nomination. Though many delegates still need to be allocated, Trump would be far closer to the majority threshold than any of his rivals.
"Florida is do-or-die for the Rubio campaign, but it looks like victory may have slipped from his grasp," Patrick Murray, the Monmouth University polling director, said Monday in a statement accompanying a poll that found Trump with a comfortable 17-point lead over Rubio.
Trump's battle in Ohio against Kasich is much closer, according to the polls. And a victory by the frontrunner there would be a knockout blow to Kasich, who has said he will drop out if he does not win in Ohio.
After largely ignoring Kasich for months, Trump has turned up the heat on Kasich. Trump has blasted Kasich at almost every recent campaign rally and in daily tweets, hitting him for supporting free-trade agreements, for campaigning out of state, and for his overall strength as a leader. "Kasich is a baby," Trump said Saturday during an Ohio rally. "He can't be president."
