(CNN) Alaska Gov. Bill Walker suspended his re-election campaign Friday night with less than three weeks to go before election day.

In a statement, Walker expressed concerns that he and Lieutenant Gov. Valerie Davidson would not win the emerging three-way race for the governor's seat.

"With more time, I am confident that Val and I could deliver a message and a campaign that could earn a victory in this election," Walker wrote in an Instagram post Friday night. "But there are only 18 days remaining before election day. Absentee ballots have already been mailed, and Alaskans are already voting. In the time remaining, I believe we cannot win a three-way race."

The fact that absentee voting has already begun and early voting begins on Monday means Walker's name will likely remain on the ballot.

Walker, an independent, endorsed Democratic nominee Mark Begich, a former US senator, citing the way Begich's priorities "more closely align" with his than do those of Republican nominee Michael Dunleavy.

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