Kyl only committed to serve through the end of the year, raising questions about the rest of McCain's term, which ends in 2022.
Ducey, a Republican, was required by law to appoint a member of McCain’s party to fill his seat. Because of the timing of McCain’s death, the governor’s appointment would theoretically serve through most of 2020. A special election is expected to be held in 2020 to serve out the remainder of McCain’s term, which ends in 2022.
"People automatically assumed that this appointment will serve through 2020," Ducey said at a Tuesday press conference. "I haven’t been able to get that assurance from Sen. Kyl yet. What I have gotten is a commitment to serve Arizona through at least this session of Congress and it’s my hope that he serves longer”
Kyl explained that he did not want to commit beyond the end of the current session because he left the Senate to spend more time with his family. He said he agreed "at least" to serve through the end of the year, but did not want to make a further commitment.
Should Kyl step down before 2020, Ducey could appoint another successor before the special election, or the seat could remain vacant until the election.
Ducey, who is running for re-election this year, denied Tuesday that he had any intention of seeking the Senate seat himself.
"I am not in the universe of potentials for this. I love the job that I have and I want to retain it,” Ducey said. " ... I’m going to stick right here.”
Kyl's appointment raises questions about whether he will continue McCain's legacy of criticizing President Donald Trump.
The former senator had previously has been critical of Trump, telling a local radio station in February, "I don’t like his style. I think it is boorish. I think he’s own worst enemy."
Asked about those comments on Tuesday, Kyl said he was referring to Trump's "desire to jump into the middle of a fire" and that "sometimes that can be detrimental to what he’s trying to achieve."
"And that’s what I said and I stand by that comment,” Kyl said.
Kyl said he does not have a relationship with the president, but noted he has been working with the administration on the president's Supreme Court nominee.
Kyl has been serving as the sherpa for Judge Brett Kavanaugh’s Supreme Court confirmation, guiding Kavanaugh through meetings with senators. Kavanaugh’s confirmation hearings began Tuesday, and Ducey noted that Kyl would be casting a to support Kavanaugh's confirmation.
Kyl, who left the Senate in 2013, was also a registered lobbyist in the nation’s capital. His clients at the firm Covington & Burling this year have included Qualcomm Inc., JW Aluminum, mining company Freeport-McMoRan, the Coalition for American Retirement and the private equity investor Gordon Sondland, who is co-founder of Aspen Capital, according to congressional lobbying disclosures.
Kyl, a former GOP whip, also worked in support of Judge Neil Gorsuch’s Supreme Court nomination for the client Judicial Crisis Network, which paid Covington $215,000 last year, according to lobbying disclosures.
Kate Ackley contributed to this report.
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