By Brad Schmidt

If John Kitzhaber resigns, it would mark the fifth time an Oregon governor has quit but the first time one has stepped down amid controversy.

The governor released a statement Wednesday afternoon saying he "has no intention of resigning" after hours of speculation -- fueled by news that Secretary of State Kate Brown cut a trip short to return to Oregon -- was calling it quits. Brown would become governor if Kitzhaber, embroiled in a growing political firestorm, stepped down.

Attorney General Ellen Rosenblum has launched a criminal investigation into allegations of corruption against him and his fiancee, Cylvia Hayes, involving Hayes' dual roles as a private consultant and an unpaid adviser to the governor on the same topics.

Kitzhaber is the longest-serving governor in state history, serving two terms from 1995 to 2002, then sitting out eight years before winning a third term in 2010. He won a historic fourth term in November.

Here's a look at the four Oregon governors who have resigned since Oregon became a state in 1859.

"The others resigned either because of a new position or because of illness," said Kerry Tymchuk, executive director of the Oregon Historical Society. Kitzhaber, he said, "would be the first to resign for neither of those reasons."

Douglas McKay, 1952: McKay, a Republican, resigned to move to Washington, D.C., to become U.S. secretary of the interior under President Dwight Eisenhower. McKay was elected in 1948 and re-elected in 1950. His decision to leave Oregon in 1952 soured voters. McKay later unsuccessfully tried to unseat U.S. Sen. Wayne Morse in 1956.

"McKay's popularity dropped after accepting the appointment, because many felt he was abandoning his state for the federal government," according to his state biography.

Frank Benson, 1910: Oregon's Republican secretary of state became governor in 1909 when Democratic Gov. George Chamberlain resigned. Benson held both posts -- and collected both salaries. Citing a recurring illness, Benson handed gubernatorial powers in 1910 to the president of the Senate. Benson died in 1911.

George Chamberlain, 1909: The Democrat served six years as governor and resigned after winning election to the U.S. Senate in 1909. He served in the Senate 12 years.

LaFayette Grover, 1877: The Democrat spent more than six years as governor, leaving office in 1877 to become a U.S. senator. The state Legislature appointed Grover to the U.S. Senate, a post he held for six years, according to a biography on the National Governors Association.

(c)2015 The Oregonian