Smith also had five assists for the Red Storm (2-1).
St. John's held a seven-point lead with 7 minutes left in the first half before McKenith took over to break the game open. She had 12 of the Red Storm's final 17 points before the half. The senior point guard got her run started by hitting a 3-pointer and capped it off with a three-point play with 30 seconds left.
St. John's led 43-31 at the break. The Red Storm dashed any hope of a Hofstra comeback by scoring 10 of the first 14 points in the second half.
McKenith, who fell two points short of her career high, had a nifty no-look pass for a lay-in by Briana Brown during the burst.
Shante Evans scored 12 points to lead Hofstra (1-2).
The two teams played last season and Hofstra came away with a 92-83 victory—only the Pride's second win in 16 meetings between the schools. Both teams opened their seasons down in Florida in a tournament last weekend.
Before Saturday's game, St. John's unveiled a banner celebrating its advancement to the regional semifinals of the NCAA tournament last season. It was the first time the Red Storm had ever made it that far.