Evan Vucci / AP

Nikki Haley’s upcoming departure from the United Nations opens up the most prominent diplomatic posting other than secretary of state, and a position that presidents have historically used to showcase rising stars or reward elder statesmen.

President Donald Trump on Tuesday told reporters he has known that Haley planned to leave his administration for “probably six months” and that he would name her replacement in the coming weeks. The names that quickly emerged following the surprise announcement included his former deputy national-security adviser, Dina Powell; the recently confirmed ambassador to Germany, Richard Grenell; and a wild-card pick: Trump’s eldest daughter, Ivanka.

“We have many people that are very, very much interested in doing it,” Trump said.

Haley has been a rarity at the senior level of the Trump administration: a powerful political appointee who drew praise from both parties and managed to navigate the tumult of the president’s first two years without being embroiled in its many scandals. Among those lamenting her departure on Tuesday were both Senate Majority Leader Mitch McConnell and the top Democrat on the Foreign Relations Committee, Senator Robert Menendez of New Jersey, who said he was “deeply concerned about the leadership vacuum she leaves and the national-security impact” of her exit.

“She was a stabilizing force,” said Lanhee Chen, a fellow at the Hoover Institution who served as a chief policy adviser for Mitt Romney’s presidential campaign in 2012. “She’s a very underestimated talent still. A lot of people don’t recognize how tough and how skillful she can be.”

Haley “was able to pick her spots,” Chen said, and occasionally veered away from Trump’s message, particularly on Russia and Vladimir Putin, without incurring the president’s wrath. But with Secretary of State Mike Pompeo and National-Security Adviser John Bolton assuming a more prominent role in foreign-policy debates than their predecessors did, Haley’s replacement may be more constrained.

“It’s likely the next UN-ambassador job will have less leeway than she did,” said Jon Alterman, a senior vice president at the Center for Strategic and International Studies.

Previous UN ambassadors have included diplomats and politicians who used the post as a springboard to higher office, like George H. W. Bush, Daniel Patrick Moynihan, Madeleine Albright, Susan Rice, and Bolton. Others, like the former Democratic presidential nominee Adlai Stevenson in the 1960s and former Senator John Danforth during the George W. Bush administration, have taken the job at the end of their careers in public life.

Here’s a look at the early possible contenders for the UN job, which requires confirmation by the Senate:

Dina Powell

Powell came to the Trump administration from Goldman Sachs and served as both a top economic adviser to the president and, more formally, as a deputy national-security adviser. Along with Gary Cohn, she was part of a group of less ideological advisers who arrived at the White House with close ties to Wall Street. Members of that group were seen as allies of Ivanka Trump and her husband, Jared Kushner, and were alternately heralded and dismissed by Steve Bannon as moderating forces. Powell did have government experience, however, having worked in the White House and the State Department during the George W. Bush administration.

“She is certainly a person I would consider. She is under consideration,” Trump told reporters outside the White House on Tuesday afternoon.

Richard Grenell

A favorite of conservatives for his brash style, Grenell served as the spokesman for the U.S. mission to the UN for the entirety of the George W. Bush administration. Trump nominated him in September 2017 to serve as the ambassador to Germany, but the Senate didn’t confirm him until April; in opposing him, Democrats cited his partisan jabs at Democratic women. He is now the highest-ranking openly gay member of any Republican administration. Within an hour of Haley’s resignation, he won the endorsement of the conservative commentator Hugh Hewitt, who had pushed aggressively for his confirmation as the envoy to Germany and called him “the obvious choice” for UN ambassador. But Grenell’s nomination would spark a more protracted fight in the Senate than Powell’s would.

Brian Hook

A veteran diplomat who has served in a staff role at the UN, Hook is one of the few top advisers to former Secretary of State Rex Tillerson who stayed in a senior role under Pompeo. He was named a special envoy to Iran in August, and Alterman mentioned him as a possible contender. “Despite being perceived as a Tillerson person, he’s managed to establish his bona fides as a person who advances the president’s agenda,” Alterman told me.

Ivanka Trump

The first daughter and senior presidential adviser was the subject of immediate speculation on Tuesday morning—after all, the UN gig would allow her and Kushner to move back to New York, as they’ve reportedly wanted to do. But the president seemed to pop that trial balloon even as he said his daughter would be “dynamite” at the UN. “I would be accused of nepotism even though I’m not sure there’s anyone more competent in the world,” Trump told reporters. And late in the day, Ivanka Trump ruled herself out. “It is an honor to serve in the White House alongside so many great colleagues and I know that the president will nominate a formidable replacement for Ambassador Haley,” she tweeted. “That replacement will not be me.”

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