The state's new No. 2, a 38-year-old attorney and vice president of a family-owned rural telecommunications company, was sworn in later Wednesday by U.S. District Judge Ted Stewart for whom Cox clerked after law school in a ceremony in the Capitol Gold Room.
Gov. Gary Herbert, who picked Cox to replace outgoing Lt. Gov. Greg Bell, thanked Bell for his years of service and welcomed "the incoming lieutenant governor. … What's your name again?"
Cox, who lives in Fairview and is in his first year in the Legislature, was indeed an unexpected choice, but one praised on both sides of the aisle.
"I've been very impressed in the year or so I've known him," said Sen. Todd Weiler, R-Woods Cross. "I think he has incredible wisdom and knowledge for his young age. … He's a smart guy, he's witty, he's got a good sense of humor, and he doesn't take himself too seriously."
Herbert explained that Cox had the necessary blend of intelligence, business experience and political chops to replace Bell.
"We know he's got the right stuff between his ears … and he's got a nice, pleasant optimistic demeanor, too," the governor said during Cox's confirmation hearing Tuesday. "He's the total package."
Cox earned his bachelor's from Utah State University and his law degree from Washington and Lee University in Virginia, graduating fifth in his class. He practiced law at Fabian & Clendenin in Salt Lake City before moving his family back to Fairview.
His father, Eddie Cox, was a mayor and Sanpete County commissioner. Spencer Cox followed in his footsteps, being appointed to the Fairview City Council before being elected mayor and then serving a term on the County Commission.
"I'm proud of Sanpete," Cox said at his swearing-in. "This is an honor not just for me but for the good people of Sanpete County. I'm grateful for my rural upbringing, for my family, for may parents, for the work ethic they taught me and the importance of public service."
Cox, who served as co-leader of the Governor's Rural Partnership Board alongside Bell, has said he wants to be a voice for rural Utah. He ran for the Utah House in 2012 on a promise of fiscal responsibility, states' rights and an infusion of resources for Utah schools.
Politically, Cox's colleagues describe him as a pragmatic lawmaker. An analysis of Cox's fairly short voting record by Brigham Young University political scientist Adam Brown found Cox to be right in the middle of the Republicans on Capitol Hill.
"From his legislative voting record, it seems Spencer Cox is about as run-of-the-mill of a Republican as Utah can produce," Brown wrote. "Voters have no more reason to love or fear him than they would any typical Utah Republican official."
Cox garnered the most attention during his time in the House when he became the first Utah legislator to call for the impeachment of Republican Attorney General John Swallow amid allegations of inside deals, improper gifts and influence peddling.
As lieutenant governor, Cox inherits an ongoing investigation by his new office into whether Swallow broke state election laws by omitting business interests and income from his financial disclosure. Cox has said he will consider his options, including possible recusal from the matter, to ensure the impartiality of the decision.
Bell, who stepped down due to financial strains created by the real-estate slump, said his advice to Cox is simple: reach out.
"I just had such great experiences out among the people, especially rural Utah," Bell said, "and they're so appreciative of you coming."
As for Cox's vacant House seat, GOP delegates from his District 58 will select a replacement to be named by the governor.