Not many details, but the recent Cook article on the Alaska Senate race had this little tidbit:
Recent Democratic polling shows the race is tied, with Sullivan not well-defined among voters. The same poll also has Trump and Biden in a statistical dead heat and puts the president's approval rating slightly underwater. However, Alaska is a state that is notoriously hard to poll and Republicans are, perhaps rightly, skeptical of such numbers. They say their own polling doesn't worry them in regards to Sullivan, but that they're taking the race seriously.
Source:
https://cookpolitical.com/analysis/senate/alaska-senate/alaska-senate-moves-likely-republican