Jets coach Paul Maurice said the 22-year-old forward would be a game-time decision. He said Ehlers missed Game 3 on Wednesday because of an illness.
Vegas won that game 4-2 and leads the best-of-7 series 2-1.
If Ehlers plays, it'll likely be at left wing on the second line with center Paul Stastny and right wing Patrik Laine. Brandon Tanev had been there during Game 3. He likely would move to left wing on the third line, and Jack Roslovic, who played in Game 3, would be scratched.
Ehlers has seven assists in 13 playoffs games. He missed Game 5 of the first-round series against the Minnesota Wild with an unspecified injury.
