Ireland's Aki nominated for Six Nations Player of the Year award
The 33-year-old centre, who was born and brought up in New Zealand, made a total of 144 metres in contact - the best of any player in the championship - as the Irish triumphed for a second successive year.
They were denied a second consecutive Grand Slam, however, by Marcus Smith's last-minute drop goal that saw England edge them at Twickenham.
England back row forward Ben Earl is also on the shortlist of four after making 73 carries, the most in this year's championship. Scotland wing Duhan van der Merwe and Italy centre Tommaso Menoncello complete the quartet of nominees.
Van der Merwe finished the campaign as joint-top try scorer, alongside Ireland hooker Dan Sheehan, with five, while Menoncello was a revelation as Italy notched up two wins and a draw to mark their best-ever Six Nations since joining the competition in 2000.
The four were the highest scoring in a fan vote for the team of the championship. Online voting continues until 2300 GMT Sunday when the winner will be announced.