Former Alaska governor Sean Parnell has endorsed Mike Dunleavy over Mead Treadwell, who served as Parnell’s lieutenant governor during his first full term.

Dunleavy announced the surprise show of support on his campaign Facebook page Tuesday evening.

Dunleavy spokesman Brett Huber declined to comment further on the endorsement beyond referring to the page, on which Dunleavy said, “I’m honored to have Sean Parnell’s support.”

Treadwell campaign spokesman Mike Robbins called the endorsement “unfortunate.”

“Sean is a good man and everybody has a right to endorse who they choose,” Robbins said. “Mead has been endorsed by thousands of Alaskans. Sean is one person who chose to endorse Dunleavy.”

Parnell, Sarah Palin's running mate in 2006, first ascended to the governor's mansion when she quit in 2009.

He and Treadwell soundly defeated Democrats Ethan Berkowitz and Diane Benson by a 22-point margin, securing a full term in 2010. During that term, Parnell admonished Treadwell for what he believed was exceeding his authority as lieutenant governor. 

In 2014, Parnell and former Anchorage mayor Dan Sullivan narrowly lost to current Gov. Bill Walker and his "unity ticket" running mate, Democratic candidate Byron Mallott. Walker is seeking re-election this year against Democrat Mark Begich and a host of Republican candidates including Dunleavy.

KTVA left a phone message for Parnell, who was not immediately available for comment on the endorsement Tuesday.

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