On the day that Donald Trump lodged his toughest attack yet on rival John Kasich, the Ohio governor defended himself in an MSNBC town hall, saying that "wallowing in the mud with Donald is not what I think is a successful strategy.”

Trump’s campaign is airing an advertisement on Ohio television accusing Kasich of being an “absentee governor” and hitting him for his time as a managing director at Lehman Brothers.

"I will say one thing about Lehman Brothers," Kasich shot back. "I ran a two man office in Columbus, Ohio. And if I bankrupted Lehman Brothers from a two man office, I should have been selected pope, not run for president." The crowd chuckled. "That's like blaming a car dealer in Lima for the collapse of GM," Kasich continued.

"Look, it's all ... it's negative and it's desperation. But the people of this state, they know me and so I'm not — I'm not concerned about it."

Kasich was speaking at a wide-ranging MSNBC town hall with Willie Geist and a crowd of constituents at Lima Pallet Company in his home state, where he addressed questions from social security to ISIS to higher education to guns.

"If I bankrupted Lehman Brothers from a two man office, I should have been selected pope, not run for president."

Kasich laughed off a statement from Geist that Trump has previously suggested Kasich would be a good vice president.

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"He'd better not say that in front of my wife," Kasich quipped, adding "I’m serious."

Kasich gave his standard answer to the vice president question, stating: "First of all, I believe I'll be the nominee. I have the second best job in America. Number one is president. Number two is governor of Ohio. And I love being governor of Ohio."

When pressed on whether he would accept Trump’s vice presidential nomination if offered, Kasich avoided a direct answer, saying, "I'm going to be the Republican nominee after we win Ohio and finish the rest of the country."

Earlier Friday, news broke that the Rubio campaign would be okay with "releasing" their supporters in Ohio to vote for Kasich, since Kasich has a better chance at beating Trump in the winner-take-all state on Tuesday, therefore preventing Trump from gathering more delegates to get closer to clinching the nomination. But Kasich did not reciprocate the offering for his supporters in Florida.

"Should I tell my voters to not vote for me?" Kasich asked. "I should tell my voters, don't vote for me, go vote for somebody else?"

"Well that's what the Rubio campaign suggested," Geist responded.

"That's kind of nuts," said Kasich. "That's something that a politician would do. I'm not going to tell my voters, go vote for somebody else. You know what else? I don't think that I have to tell them anything. Let them figure it out. But I mean, would that be the most bizarre thing? ‘You like me but please don't vote for me. Go vote for somebody else.’ Let's just let it all run its way."

"I believe I'll be the nominee."

Kasich has repeatedly acknowledged that a victory for him in Ohio could lead to a contested Republican National Convention in Cleveland this summer, often adding how such a scenario could result in an educational opportunity for students. But at the MSNBC town hall, he maintained that he could "absolutely win enough and go into the convention with the greatest number of delegates. That absolutely can happen."

"I think it's very hard for anybody to get there with the right number of delegates to clinch the nomination," Kasich added. "But you know, you get there and you have the delegates there and they take a look at who's running and who's in the arena and then they make a pick. But I could go in there stronger than anybody else. That's not inconceivable."

Kasich returns to Ohio touting his strong record on job creation in the state, but he was asked about a few steel plants that are scheduled to close in Lorain, Ohio at the end of the month.

"First of all, you have to rush in there and find out what you can train them for," Kasich responded. "But we're up in Ohio 63,000 manufacturing jobs since I've come into office.” Kasich blamed part of the situation on a violation of trade agreements – "If I'm president we're not going to put up with that nonsense anymore. We're going to have an expedited process. When we see a violation of these trade agreements, we're going to act on them immediately," he said.

Kasich’s town hall took place in the Ohio town of Lima, where a young man was recently shot and killed at a convenience store. Kasich said he wasn’t aware of the details of the case, but that shootings like this are not a "gun problem" because "people have a right to defend themselves. I think people have a right under the Second Amendment to collect guns, to hunt."

"I just don't believe that passing laws to restrict guns is going to have any impact," he continued. "I think it is fundamentally a problem with the people who engage in this kind of violence."

Ohio’s primary is on March 15 and Kasich has said that if he does not win, he will exit the presidential race.