WASHINGTON — (CNN) Former GOP presidential nominee Mitt Romney is again warning his party of the dangers of a Donald Trump nomination, saying a three-man race likely paves the way for the New York billionaire to capture the nomination on the first ballot of this summer’s GOP convention in Cleveland.

The former Massachusetts governor, in an interview on “The David Gregory Show” podcast says Tuesday’s New York primary is an important moment in the primary fight.

“If (Gov. John Kasich and Sen. Ted Cruz) are both going at it aggressively until the very end then I think Trump gets it on the first ballot,” Romney said.

Both Cruz and Kasich trail Trump badly in the delegate count, but only Cruz has a mathematical shot of catching Trump.

The Texas senator’s campaign has also proven far more effective in organizing delegates who would be likely to support him in Cleveland in the event of a contested convention.

Romney argues that even if Trump were to fail to reach the magic number of 1,237 delegates needed to capture the nomination going into Cleveland, he could still wrangle the votes by wooing delegates.

“My guess is some delegates might like to fly around on Air Trump or perhaps get a membership to Mar-a-Lago,” Romney told Gregory, a CNN political analyst, referring to the Trump owned resort in Palm Beach, Florida.

Over the weekend, Trump boasted of his ability to persuade wavering delegates to come to his side, but insisted he won’t engage in such tactics because he thinks it’s wrong.

The Trump campaign has been criticized for being woefully unprepared for the organization of delegates required by a presidential campaign.

The GOP front-runner argues the delegate system and GOP rules are undemocratic and should be changed.

Romney, the party’s 2012 nominee, again warned that Trump will lose badly this fall should he be the nominee.

Responding to Trump’s criticism about the GOP delegate rules, Romney was dismissive, saying the rules were well known more than a year ago.

And, taking another swipe at Trump, he told Gregory it’s a good thing the rules are difficult.

“After all these rules are a lot simpler than the rules of foreign affairs or the rules of our economy. And if you want to be president, you are going to have to deal with things far more complicated than republican delegate rules,” he said.

Romney’s entire interview on “The David Gregory Show” will post Friday.

In it, he speaks about how Trump became a political phenomenon, faith in public life and his father’s 1968 run for the White House.

“The David Gregory Show” podcast is available on iTunes and other podcasting applications.