Murkowski had trailed Tshibaka initially in the state’s first general election using ranked-choice voting. Tshibaka has the backing of former President Donald Trump.
Murkowski, a senator since 2002, has 43.3% of the first-place votes while Tshibaka has 42.7%. Democrat Pat Chesbro has 10.3%, according to the results.
Under ranked-choice voting, voters pick their top candidates regardless of party.
If no one wins 50% of the first-place vote in the first round of tabulations, the last place candidate is eliminated and his or her second place votes are tabulated. This continues until a candidate has more than 50%.
The elections division plans to tabulate all of the votes and release the results by 4 p.m. Wednesday.
Gov. Mike Dunleavy still has more than 50% of the votes in his race but his lead has dwindled. The latest numbers show the Republican governor has 50.3% of the first-place votes.
Democrat Les Gara has 24.1% of first place votes while former Republican Gov. Bill Walker, who ran as an independent, has 20.7%.
In the state’s only House race, Democrat Rep. Mary Peltola remains ahead of her challengers with 48.7% of first place votes. Republicans Sarah Palin and Nick Begich have 25.8% and 23.4% respectively.
Peltola won a special election in August to replace the late Don Young, who was longest-serving Republican in Congress before his death in March.
Although Palin has been deeply critical of the ranked-choice voting, which allowed the RINO candidate Begich to advance past the primary, her standing may benefit considerably if she winds up being the second choice of more centrist Republicans. However, it remains to be seen whether it is enough to put her over the top.