WASHINGTON (Reuters) - U.S. President Donald Trump promised to move quickly to nominate a successor to Dan Coats, who leaves his position as Director of National Intelligence on Aug. 15.

FILE PHOTO: U.S. Representative Michael McCaul (R-TX), the Chairman of the Homeland Security Committee, speaks to the news media after attending a closed House Republican Conference meeting with the U.S. President Donald Trump among others at the U.S. Capitol in Washington, D.C., U.S., June 19, 2018. REUTERS/Leah Millis

Here are three potential candidates who could be named after Trump last week dropped his choice of John Ratcliffe to be spy chief after questions arose about the congressman’s lack of experience and exaggerations in his resume, according to administration officials and media reports.

U.S. REPRESENTATIVE MIKE MCCAUL - McCaul, 57, has never served on the House of Representatives Intelligence Committee but the eight-term congressman was chairman of the Homeland Security Committee for six years and is currently the top Republican on House Foreign Affairs.

McCaul has backed Trump at key points, including declaring shortly before Election Day in November 2016 that Trump’s opponent in the White House race, Democrat Hillary Clinton, had committed treason by mishandling emails.

He was among the first members of Congress to support Trump’s 2017 ban on travelers from some majority-Muslim countries and was said to have been a potential pick for secretary of Homeland Security in Trump’s cabinet.

More recently, McCaul has shown a willingness to work with Democrats who control a majority on the Foreign Affairs panel. He has questioned some Trump decisions, such as cutting off aid to countries in Central America because thousands of their citizens sought asylum at the U.S. border with Mexico.

One of the richest men in Congress, McCaul was chief of counterterrorism and national security for Texas’s branch of the U.S. Attorney’s office before coming to Washington in 2005.

PETE HOEKSTRA - Hoekstra, 65, is the U.S. ambassador to the Netherlands and a former nine-term member of the House who spent more than six years in top positions on the intelligence committee.

He became a lobbyist after leaving the House in 2011.

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Hoekstra advised Trump on national security and co-chaired his 2016 presidential campaign in Michigan, helping deliver a state that had not backed a Republican presidential candidate since 1988. Hoekstra’s name came up previously as a potential nominee for CIA director.

Hoekstra as born in the Netherlands before moving to the United States as a young child.

His tenure as ambassador got off to a rocky start in 2018, when he dismissed as “fake news” unsubstantiated anti-Muslim claims he made in 2015. He apologized after a Dutch journalist played a videotape of Hoekstra saying “the Islamic movement” had put Europe in chaos, with cars and politicians “being burned” in the Netherlands and the country scarred by “no-go zones.”

DEVIN NUNES - The eight-term Republican congressman rose to national prominence after Trump’s election and has been an ardent defender of the president. Nunes, 45, served on Trump’s transition team and has accused U.S. intelligence officials of abusing their power to target the president and his circle.

He served as chairman of the House Intelligence Committee from January 2015 to January 2019, and has since been its Republican ranking member.

In early 2017, as the committee investigated Russia’s role in the 2016 election, Nunes made a mysterious visit to the White House, after which he accused former President Barack Obama’s administration of revealing the names of Trump associates whose conversations had been swept up in other government surveillance efforts.

That incident prompted an ethics investigation during which Nunes recused himself from the committee’s Russia investigation. The probe ended without action against Nunes.

An early and vocal critic of special counsel Robert Mueller’s investigation of the 2016 election, Nunes released a memo in February 2018 accusing the Federal Bureau of Investigation of conspiring against Trump. In March 2018, he and his fellow committee Republicans announced they had determined that Russia had not sought Trump’s election in 2016, despite intelligence agencies finding that Moscow had sought to boost Trump’s chances of defeating Clinton.

He also has sued Twitter, Twitter parody accounts and local media, saying they have been unfair to him.

Trump has praised Nunes as “a true American Patriot” and suggested he deserved the Medal of Freedom, the highest U.S. civilian honor.