People wait in line to hear Republican presidential candidate John Kasich speak at a campaign stop at the Fuyao Glass America plant in Moraine, Ohio on Friday, March 11, 2016. (AP Photo/John Minchillo)

MORAINE, Ohio -- Marco Rubio's campaign spokesman said Friday that the best way to block Donald Trump from winning the Ohio primary next week would be for Rubio supporters there to vote for John Kasich, Ohio's governor, whom polls show locked in a tight battle with Trump here.

Kasich is not returning the favor, in Rubio's home state of Florida or anywhere else.

After a rally with 1,000 supporters at a glass factory outside of Dayton, Kasich dismissed a question of whether he would ask his backers to vote for Rubio in Florida.

"If I've got supporters somewhere in the country, and I'm on the ballot, they kind of ought to vote for me," Kasich said, adding, "I mean, what kind of deal would it be if I told my people, 'don't vote for me'?"

Kasich is running far behind Trump, Rubio and Ted Cruz in Florida, polls show. Rubio is trailing badly in Ohio. Ceding votes to each other could help Kasich and Rubio deny Trump delegates in their respective home states, because each state is holding a winner-take-all primary.