Arizona Gov. Doug Ducey on Tuesday announced he had chosen Jon Kyl, once one of the most powerful Republicans in the U.S. Senate, to succeed the late Sen. John McCain.

In a news conference at the Arizona Capitol, the Republican governor said he expected 76-year-old Kyl to "hit the ground running" when he arrived in Washington, D.C., Tuesday evening.

"It's not the time for newcomers, and now is not the time for on-the-job training," Ducey said, adding that he'd "kept coming back to one name and one person" as he weighed appointment options.

"Sen. Kyl is a beacon of integrity, highly regarded by people on both sides of the aisle and able to work across party lines to get results," he said. "There's a reason he was considered one of the best senators in the country."

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Kyl will likely be sworn in Wednesday. He has agreed to serve at least through the end of the year.

"I'm accepting this appointment to fill the seat vacated by the passing of my dear friend because of my sense of duty to the state I love and the institution of the Senate which I served for 18 years, and because the governor asked for my help," Kyl said at the news conference.

"…There is much unfinished business on the Senate's calendar."

Supreme Court nomination fight looms

At the top of the list: confirmation hearings for Supreme Court nominee Brett Kavanaugh, which began Tuesday.

A Senate committee is pushing for a vote later this month to send Kavanaugh’s nomination to the full Senate, hoping to get him on the bench before the midterm elections.

"Sen. Kyl has been working closely with the White House on the senate confirmation of President Donald Trump's nominee," Ducey said. "Now, Sen. Kyl can cast a vote for Kavanaugh’s confirmation."

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The governor also said he wanted to appoint someone who could quickly step into and lead conversations about critical Arizona issues, from water and natural resources to Native American relations.

Ducey and Kyl, whom Ducey has long called a mentor and model public servant, have forged a close bond and are like-minded, pro-growth conservatives.

"The fact is every single day that Jon Kyl represents Arizona in the U.S. Senate is a day that our state is being well-served," Ducey said.

"At the memorial here in the state Capitol last week, Sen. Kyl spoke of how Sen. McCain always put the interests of Arizona and American before all else. Sen. Kyl has done the same throughout his own service to our state and nation and will do so again," he said.

Kyl, a respected figure among seasoned Republicans, served alongside McCain during his 18 years in the U.S. Senate. He retired in 2013 after becoming minority whip, the second-highest-ranking Republican.

After leaving the Senate, Kyl joined the high-powered Washington, D.C., law firm Covington & Burling, where he lobbies for clients on issues including taxes, health care, defense, national security and intellectual property.

Last year, he was the "sherpa" for Jeff Sessions' contentious nomination to become attorney general.

At the press conference, the governor was asked about his decision to appoint a white man, after a former McCain staffer last week spoke of the late senator's desire to see more women and minorities advance in the Republican Party.

Ducey said, simply: "I'm picking him because he's the best possible person."

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'I had no intention of returning'

In the 13 months since McCain received his brain-cancer diagnosis, the appointment decision weighed heavily on Ducey, who is seeking re-election this fall.

Conservatives in Arizona and the U.S. wondered whether the governor would pick someone in McCain's image or go for a political outsider like Trump.

The governor refused to publicly discuss any potential appointment and condemned those lobbying for McCain's seat while the late senator was still serving. That changed on Aug. 25 in the hours following McCain's death.

In a conversation with Kyl that day, the governor told him he wanted to name him as McCain's successor. Kyl got back to Ducey the next day after consulting with his wife and committed to finishing out the year.

"When I left the Senate almost six years ago, I had no intention of returning," Kyl said Tuesday, saying he'd been focusing on his family and wanted to continue to do so.

"I'm willing to serve, certainly, through the end of the session … but I don't want to make a commitment beyond that," he said.

Kyl did not address whether he would return to his lobbying career after serving in the Senate. Senators typically must wait two years after leaving office to lobby for compensation.

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'A great tribute to John'

In the minutes after Ducey announced his decision, many prominent conservatives praised his choice. Some Democrats criticized the decision, pointing to Kyl's history of opposing abortion rights.

As Ducey heads toward the general election, the Kyl appointment could help appease independents disenchanted with the performance of the president and GOP leadership.

In Kyl, they may see a veteran legislator with experience navigating complex policy issues and a willingness to compromise.

It was unclear if the McCain family had influenced the appointment process. The governor on Tuesday said he'd had a "very positive" conversation with McCain's wife, Cindy, who later expressed support for the appointment on Twitter.

"Jon Kyl is a dear friend of mine and John's," she wrote. "It's a great tribute to John that he is prepared to go back into public service to help the state of Arizona."

The Governor's Office said Ducey would submit a certificate of appointment to the U.S. Senate secretary. An aide will fly the paperwork to Washington, D.C., and hand-deliver it to the secretary's office.

If Kyl opts to step down after the end of the session — which Ducey said he hopes won't happen — the governor would be required to appoint another replacement.

Ducey has said he is not interested in the seat.

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