Dunleavy is the likeliest just by virtue of Alaska being ungovernable.
Guessing there's a reason why Tony Knowles (D) was the last AK Governor to serve 2 full terms.
Since then:
Daddy Murkowski (R), 2002-2006: lost BIGLY in GOP Primary in 2006.
Sarah Palin (R), 2006-2009: resigned for some weird reason. We still don't know why she upped & quit.
Sean Parnell (R), 2009-2014: served out the remainder of Palin's term & won election to full term in 2010 landslide; lost reelection in 2014.
Bill Walker (Ind), 2014-2018: didn't seek reelection in 2018.
Mike Dunleavy (R), 2018-
Aren't the oil prices in Alaska all over the place and everyone always blames the governor? Probably why Palin quit; can't continue to build a national profile if you get hit with a wave of unpopularity back home.