The Toffees are two points behind fifth-placed Arsenal and six off fourth-placed Tottenham, who have played a game more, while fierce rivals Liverpool lurk in seventh.
Jagielka has only an outside chance of featuring against Stoke on Saturday but with just nine Premier League games left, the England international wants manager David Moyes to sanction all-out attack.
"We need to win games now," Jagielka told the Liverpool Echo.
"If we were to draw I'm not saying it would be the end of the season but we have to go out ultra-positive and really take it to teams and see how we go. It might make the manager's decision-making a little bit easier.
"The manager can be ultra-positive now and throw the shackles off."
December's last meeting between the sides was a feisty one, with Marouane Fellaini handed a retrospective punishment for headbutting Ryan Shawcross after what the Toffees claimed was provocation throughout the match.
Fellaini served a three-match ban and, along with team-mate Steven Pienaar, is also suspended for the Potters' visit this weekend.
"Obviously we didn't enjoy the way it was when we played at Stoke," Jagielka added.
"I don't think we got any help from the officials at all. You can't condone
what Felli did but in the build-up he was getting wrestled all the time.
"We won't look back at the game though because now we need to concentrate on being positive and getting the right results."