Ohio Gov. John Kasich kept his presidential hopes alive Tuesday with a win in his home state, staving off Republican frontrunner Donald Trump as he landed all of the state's 66 delegates. He vowed to stick to his relentlessly upbeat messaging as he stays in the hunt.

It was the first victory for Kasich's campaign this year, but it was a crucial one: Losing Ohio would have forced Kasich to abandon the race, just as Florida Sen. Marco Rubio was knocked out of the contest when he lost the Sunshine State.

Kasich still faces a daunting deficit in the race for delegates, badly trailing Trump and Texas Sen. Ted Cruz. But he is now the establishment's last hope to halt Trump's march to the nomination, and Kasich pledged to take the fight to the Republican National Convention if needed.

He's relied on a sunny, positive message throughout his campaign and an appeal to moderates and independents. Since his second-place finish in New Hampshire, though, he had failed to gain much traction in the race. His supporters hope Tuesday's results change the dynamic.

He said at his campaign rally in Berea, Ohio that he'll be a consensus-builder who can fix the nation's problems.

"You want to believe again that we can have job security. You want to believe that wages can rise. You want to believe that our children can ultimately have a better America than we got from our mothers and fathers," said Kasich.

"I will not take the low road to the highest office in the land," he added.

Voters in five major states cast ballots on Elimination Tuesday, which is shaping up to be the most pivotal day in the primary calendar. Florida, Ohio, Illinois, North Carolina and Missouri held primaries, and hundreds of delegates are up for grabs. It's also the first time huge troves of delegates are at stake in winner-take-all Republicans contests.

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