Republicans delivered a split verdict between Donald Trump and Ted Cruz in the latest round of presidential voting, offering fresh evidence of the turmoil still roiling the party after 19 states have had their say.

Trump, still the front-runner in the delegate count, won Kentucky and Louisiana on Saturday. Cruz, cementing his claim to be the Trump alternative, captured Kansas and Maine.

Trump said it was time for Marco Rubio to exit the race. But the Florida senator insisted he was still fixing to win his home state of Florida on March 15.

The campaign tally sheets so far: 12 wins for Trump; six for Cruz and one for Rubio.

Anyone but Trump

With the Republican race in chaos, establishment figures are frantically looking for any way to derail Trump, perhaps at a contested convention if no candidate can get enough delegates to lock up the nomination before the party meets in July.

Mitt Romney, the 2012 Republican nominee, pushed the idea of a convention fight during a blistering anti-Trump speech this week. Romney's address raised questions about his own willingness to seek the nomination at a convention.

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Romney fueled the speculation further during an appearance Sunday on NBC's Meet The Press

While he said he "can't imagine" being elected by delegates at the party's Cleveland convention in July, he added, "I don't think anyone in our party should say, 'Oh no, even if the people in the party wanted me to be president, I would say no to it.'"

Republicans warm to Cruz

For months, Republican leaders have linked Trump and Cruz together, arguing that neither could win in November's general election. But the Republican elite's fear of Trump could be stronger than its disdain of Cruz, who has cultivated a reputation for tangling with his own party's leaders.

South Carolina Sen. Lindsey Graham, also appearing on NBC, said Cruz "has made the best case thus far that he can be the alternative to Trump." Graham, who ended his own White House bid earlier this year, said Rubio and Ohio Gov. John Kasich "have got to decide among themselves" whether they can be a realistic alternative to front-runner Trump.

Trump, at a post-election news conference in West Palm Beach, Fla., flatly predicted he'd win the nomination outright before the convention, likening it to a knockout blow in boxing.

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"The way I guarantee victory is get enough delegates, so I don't have to worry," he said.

Rubio adds Puerto Rico delegates

Cruz, for his part, said his strong showing was "a manifestation of a real shift in momentum."

"What it represents is Republicans coalescing, saying it would be a disaster for Donald Trump to be our nominee," the Texas senator said.

Both men were itching to go at it one-on-one.

"Oh, do I want to run against Ted," said Trump, ticking off a list of large states where he said Cruz had no chance. "That will be easy."

​Cruz won at least 64 delegates Saturday, making a small dent in Trump's lead for Republican convention delegates. Trump picked up at least 49, Rubio at least 13 and Kasich nine.

Rubio picked up all 23 delegates from the winner-take-all Puerto Rico race.

Rubio said in an interview Sunday that he "campaigned in Puerto Rico as a conservative" and still garnered more than 70 percent of the vote in an "open primary."

The senator says that "is evidence I can take conservatism to people who don't normally vote Republican" and win their support.

Overall, Trump led with at least 378 delegates, Cruz had at least 295, Rubio 151 and Kasich 34. It takes 1,237 delegates to win the Republican nomination for president.