Which four world leaders would a President Buttigieg meet with this week at the United Nations? CBS News Political Correspondent Ed O’Keefe asked him on Monday during an interview aboard his campaign bus in Waterloo, Iowa.

Here are some highlights from his answer:

“1a and 1b,” he said, would be “[German Chancellor] Angela Merkel, or [French President] Emmanuel Macron, who in many ways I think is emerging as a kind of successor generation leader in Central Europe. I think we need to shore that up and have that conversation.”

His second world leader would be Iranian President Hassan Rouhani. “We need to engage with Iran,” he said. “Now, I wouldn’t do it without some kind of sense that there was momentum, but if our respective diplomatic relationships could produce even the smallest incremental trust building measure, I think that would justify a conversation about how we could cause tensions in that region to go down, rather than up.”

Asked if that means he’d be willing to lift sanctions on Rouhani and other world leaders, he said: “I think we could find a way if the focus of U.S. policy were to de-escalate, rather than ratchet up tension.

Number 3? Nayib Bukele, the president of El Salvador, someone who “represents a part of the country — the world, Central America, where we have a lot at stake.”

And fourth would be Chinese President Xi Jinping. “The China challenge is going to be one of the dominant issues for the United States in my lifetime,” Buttigieg said, adding later that, “I think we need to have a very frank conversation, about ways in which we will adjust the future of the relationship. And, that may include an orderly decoupling of some of our technological interdependencies.”

“This is not just about trade. This is about technology security and stability,” Buttigieg said.

Watch “CBS This Morning” Tuesday morning and CBSN later in the day for highlights.

FROM THE CANDIDATES

ANDREW YANG

CBS News Political Unit Associate Producer Ben Mitchell reports that Andrew Yang is ramping up his presence in Iowa. The 2020 Democratic candidate and entrepreneur opened two new offices in the state on Sunday, following weeks of expanded hiring that included a new strategist focused on early states.

The office openings came on the heels of a relatively good showing for Yang in the newest Des Moines Register/CNN poll. While he’s only polling at 2%, he also saw a 9-point increase in an aggregate measure that takes into account voters’ first and second choices, as well as candidates they’re actively considering — a jump second only to Elizabeth Warren.

At all of his events, he kept hitting on the idea that “Iowa is magic,” saying that voters in that state can actually make a real change in the direction of a country and calling it “one of the few states where democracy actually works.” In an interview with CBS News, Yang said,”We are going to compete in Iowa and contend the whole way.” Yang added, “We’re going to put up a record fundraising number in [the third quarter of the year], we’re going to have the resources to compete everywhere in the country. ”

EARLY STATES

DOWN SOUTH

Votes were canceled in the U.S. House of Representatives as hundreds of family members and friends assembled in Charleston to celebrate the life of Dr. Emily Clyburn, wife of House Majority Whip James “Jim” Clyburn. CBS News Campaign Reporter LaCrai Mitchell says a similar gathering took place in her honor in Columbia on Sunday, where guests included Nancy Pelosi, John Lewis, Kamala Harris, Elizabeth Warren and Tim Ryan.

During Monday’s service, an emotional Clyburn held back tears as he described life with his partner of 60 years. He told a story of Emily teaching him long ago the importance of bragging gently when you win and weeping softly when you lose. “That’s the reason you don’t see me bragging a whole lot and I’m not gon’ let you see me cry,” said Clyburn.

Dozens of congressional members, along with Joe Biden, Marianne Williamson and Ryan, were also in attendance.

OUT WEST

Pete Buttigieg and Tom Steyer will headline a fundraiser for the Nevada State Democratic Party on Saturday, joined by Representative Ro Khanna (campaign co-chair for Bernie Sanders), Carolyn Booker (mother of Cory Booker) and Douglas Emhoff (husband of Kamala Harris). CBS News Campaign Reporter Alex Tin says the first annual “Keep Nevada Blue” event comes after a banner year for the party in which they took control of the governor’s mansion, the state legislature and a handful of congressional seats.

Among those not attending will be Marianne Williamson, who was initially slated to speak at the Reno gathering. This comes not long after Williamson’s Nevada state director parted ways with the author’s presidential bid, citing “new opportunities.”

ISSUES THAT MATTER

GUN DEBATE

Eight of the top presidential candidates teamed up together for the second video in the Giffords PAC’s #GunSafetySeries, notes CBS News Political Unit Associate Producer Ellee Watson. The video comes as President Trump is expected this week to confer with Congress about what kind of gun control legislation he would be willing to sign.

After the mass shootings in Dayton and El Paso, Mr. Trump indicated he’d be willing to pass expanded background checks. Since then, he has backtracked and said the U.S. already has “very, very strong background checks” for gun purchases.

WOMEN IN POLITICS

On Monday, more than 450 women and men gathered in New York City to hear from the president of EMILY’s List along with several lawmakers and current candidates running for office in 2020. The progressive political action committee is hoping to build off the momentum that lead to a record number of women being elected to office in 2018 as they focus on 2020.

Maine state House Speaker Sara Gideon, who was in attendance, is seeking to unseat Sen. Susan Collins. In her pitch to potential donors, Gideon argued a vote for Collins is a vote for Majority Leader Mitch McConnell and the Trump administration.

Meanwhile, Theresa Greenfield, who is seeking to unseat Sen. Joni Ernst in Iowa, warned about efforts to cut social security and Medicaid, giving an early preview of what Democratic messaging will be for 2020. While Mr. Trump was brought up on several occasions, he was not the main focus for much of the event, where candidates remained focused mostly on the topics of health care and protecting the middle class.

EMILY’s List President Stephanie Stephanie Schriock told CBS News Political Unit Associate Producer Sarah Ewall-Wice their goal is to be “joyful warriors” rather than focusing on fear.

CONGRESSIONAL COVERAGE

IN THE HOUSE

There may be one more election in 2019. With Republican Representative Sean Duffy officially resigning Monday due to family health concerns, Wisconsin Democratic Governor Tony Evers announced that, if necessary, a primary for the 7th Congressional District will be held December 30, 2019. A general election is set for January 27, 2020.

According to state law, the earliest a primary could happen would be December 24, 2019, which a governor’s office spokesperson told CBS News Political Unit Broadcast Associate Aaron Navarro was “problematic” because it would occur on Christmas Eve, a state holiday. There were thoughts the special election could have also been held in conjunction with the state’s nonpartisan spring elections, but the spokesperson said that would’ve kept Duffy’s district without a representative for more than six months. North Carolina’s 9th Congressional District, the last high-profile special election this year, was without a representative for a bit over nine months.

Down in Texas, fresh off unveiling their plan to flip the state blue in 2020, Texas Democrats announced that Democratic National Committee Chair Tom Perez will be a keynote speaker at their annual Johnson-Jordan dinner in October. In a Monday press release, they said the DNC is “planning unprecedented investments to help flip Texas,” and a DNC spokesperson told CBS News Political Unit Associate Producer Eleanor Watson a couple weeks ago that they increased their investments in the state party by 33% compared to this time in 2015.

“With unprecedented investment from national partners like the Democratic National Committee, this is our moment,” said Texas Democrats’ Chair Gilberto Hinojosa.

Earlier this month, Trump Campaign Communications Director Tim Murtaugh told Navarro they encourage more Democratic spending in Texas. “We’ve been hearing about how Texas is going to turn blue for the last 30 years. Right?” he said. “They can’t win Texas, Donald Trump is going to win Texas. That’s money they can’t spend in Michigan. So, great.”

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