The Democratic presidential primary debate on Tuesday will feature Vermont Sen. Bernie Sanders’ return to the campaign trail after a health scare and one fresh face.

The field of candidates expected to take the stage in Westerville, Ohio, is the largest to date, with a dozen qualifying under the rules set by the Democratic National Committee. The matchup includes billionaire activist Tom Steyer, who will be making his first appearance on a debate stage. It also features the return of Hawaii Rep. Tulsi Gabbard, who did not qualify for the September debate. After threatening to boycott Tuesday’s debate, she reversed course Monday, saying she would attend after all.

Sanders, meanwhile, will take the stage two weeks to the day after he suffered a heart attackwhile campaigning in Nevada.

President Donald Trump’s personal attorney Rudy Giuliani on Monday denied being involved with a Ukrainian oligarch whose ethical issues have dovetailed with the ongoing impeachment inquiry into the president.

Giuliani also told NBC News he was not planning on visiting Dmitry Firtash, who is currently wanted on corruption charges in the U.S., during a trip to Vienna he planned last week. He said he could not speak for his two Soviet-born business associates, Lev Parnas and Igor Fruman, who were arrested last week on campaign-finance charges in Virginia as they were about to board one-way flights to Vienna. Giuliani has said their similarly timed Austrian trips were not in conjunction.

“I wasn’t planning to go see him,” Giuliani said. “That was the last thing from my mind on why I was going to Vienna. There was a very important reason I was going that I’m not at liberty to disclose right now that will make it quite clear [Parnas and Fruman] were not fleeing. And I don’t know, I can’t speak for them, they have their own businesses. I actually do two things with them. I represent their company, and they help me find people. But I’m pretty sure they were going just for the purpose I knew about.”

Giuliani insisted he has “nothing to do with Firtash,” whose legal team includes Joe diGenova and Victoria Toensing, the pro-Trump husband and wife attorneys who Fox News reported were “working off the books” with Giuliani as part of his Ukrainian venture.

“So, Firtash, I know nothing about,” Giuliani said. “I’m not going to answer any questions about because I’m probably going to get it wrong, and you can ask them.”

Giuliani also said he has “never” brought up Firtash’s extradition battle with Trump.

“I’m not even sure the president is aware of him,” Giuliani said. “I think if you asked the president ‘who is Dmitry Firtash?’ He would say ‘I don’t know.’ As far as I know, we’ve never discussed him.”

One of Ukraine’s wealthiest businessman, Firtash has battled extradition charges to the U.S. for the past two years as the Department of Justice seeks to prosecute him over allegations he bribed Indian officials to land a lucrative mining deal. Federal prosecutors labeled him as an “upper-echelon [associate] of Russian organized crime.” Firtash has denied that label and the charge, fighting them from Vienna, where he has lived for the past five years.

Parnas has been working for Firtash’s legal team as a translator, a spokesman for DiGenova and Toensing told NBC News. The spokesman denied that Parnas’ Vienna trip involved Firtash.

As NBC News reported last week, Parnas and Fruman sought to change the leadership at Ukrainian state-run gas company Naftogaz at the same time they were working with Giuliani to uncover information related to former Vice President Joe Biden and his son Hunter’s Ukrainian business ties, an effort that is now the subject of the House impeachment inquiry. Naftogaz’s existing leadership was hostile toward Firtash’s past energy dealings. Giuliani last week denied any involvement with the efforts aimed at Naftogaz.

House Democrats subpoenaed Parnas and Fruman for documents and testimony as part of the impeachment inquiry, which began soon after it was revealed that Trump asked his Ukrainian counterpart in July for “a favor” that included probing the Bidens and investigating a conspiracy involving the 2016 election

Giuliani has repeatedly highlighted an affidavit former Ukrainian Prosecutor Viktor Shokin filed in behalf of Firtash in which Shokin blamed his ouster on his investigation of Burisma, the Ukrainian gas company affiliated with Hunter Biden. Backed by much of the international community, the former vice president pushed for Shokin’s ouster over his ineffectiveness at cracking down on corruption. The probe of Burisma had been dormant for more than a year by the time Shokin was fired and there has never been evidence that either Biden acted inappropriately.

Giuliani told NBC News he had “nothing to do with the preparing of the affidavit” and said he has more evidence to base his claims about Biden on than that document, including an interview with Shokin.

“This is a smear job. The Firtash thing is a smear job. I have nothing to do with him. The president has nothing to do with him,” Giuliani said. “The fact is, I know his case because it’s very famous. I know the contending positions on both sides of the case, but I have no involvement in it beyond hearing about it and obviously being given an affidavit.”

“And all I did was outline the parts of that affidavit that pertain to me,” he continued. “I have no idea if the rest of the affidavit is relevant, truthful. I do know the parts of the affidavit that I put out I can support with independent evidence, plenty of independent evidence.”

Allan Smith

Allan Smith is a political reporter for NBC News.

Tom Winter contributed.

Ahead of Tuesday’s Democratic presidential debate, Julián Castro picked up an endorsement from actor John Leguizamo, was mimicked by ‘Hamilton” creator Lin-Manuel Miranda and took his own comedic turn at his twin brother’s expense.

Leguizamo, most recently nominated for his performance in the docudrama “When They See Us”, has been on national tour with “Latino History for Morons,” his one-man show that uses his comedic and acting talents to educate the country about its Hispanic and Latin American history. The show also was a Netflix feature.

Although the endorsement was announced Monday, Leguizamo had made his Democratic presidential candidate preference clear over the summer when Stephen Colbert asked his choice.

“Julián Castro. I love that cat. I met him 10 years ago. He was what 30 back then? He was so brilliant, so smart, so composed. … I want him to win, plus he’ll make Stephen Miller so angry,” Leguizamo said. Miller is a policy adviser to Trump behind much of the administration’s hard-line immigration policies.

On Monday, Julián Castro’s campaign released a list of 58 endorsements which include Latina actor and comedian Cristela Alonzo, current and former state and local legislators, former White House officials and community activists.

Castro’s campaign is struggling; though his campaign said he has had his best fundraising quarter, he has not met the polling requirement he needs to qualify for November’s debate.

Castro will be among the 12 Democratic candidates participating in Tuesday’s debate in Ohio.

His campaign announced that on Tuesday, hours before the debate, Castro would visit a Mennonite church in Columbus, Ohio, and meet with Edith Espinal, an undocumented immigrant who has been in the U.S. for 20 years and is facing deportation despite support from the community and some elected officials. She has sought sanctuary at the church and has asked the 2020 presidential candidates to meet with her.

Monday’s endorsements followed a weekend of activities and some media attention, including some ribbing from Lin-Manuel Miranda who portrayed Castro on “Saturday Night Live” and pitched himself as “young, diverse. I’m Latinobama.” Miranda’s appearance followed criticism of the show after it did not include Castro, the only Latino candidate in the race, in a debate sketch during the season premiere on Sept. 28.

The Castro brothers spoke Sunday at The New Yorker Festival, an event held by New Yorker magazine. Julián Castro walked onstage to “My Shot,” a song from “Hamilton,” created and starring Miranda.

Castro got in the act himself over the weekend, but rather than mock himself, he chose the next closest thing, his identical twin, Rep. Joaquín Castro, D-Texas.

Castro helped the Society of Professional Journalists, San Antonio, raise money for journalism scholarships with an appearance in the 2019 Gridiron Show that was themed “Enemies of the State.” The satirical show pokes fun at current events and newsmakers, and Castro and his brother have participated in previous years.