Story of the match
Wrexham had a glorious chance just two minutes into the match as a header by Aaron Hayden found Mullin and his shot was parried away by goalkeeper Sam Slocombe.
Wootton played a lovely left-footed through ball to Mitchell and he worked his way down the left only to see his cross cleared by Max Cleworth.
On 25 minutes, Jordan Davies combined with Mullin on the right and his pull-back to Luke Young sailed over the bar.
The Red Dragons thought they had taken the lead through James Jones, but Jake Hyde was ruled to have been offsides in the buildup.
A minute before halftime and it was the visitors who were in front. Wootton got on the end of a floated cross by skipper Kyle Cameron and he beat Rob Lainton with a looping header.
Ten minutes later, the Red Dragons were level. Jones' cross was met by Mullin and the former Cambridge frontman headed past Slocombe on his home debut.
The hosts were nearly ahead just minutes after a neatly worked move by Mullin, Hyde and Davies ended with Jones seeing his shot held by the Notts County goalkeeper.
Ruben Rodrigues then had an opportunity, but he fizzed his shot just over. Late on, the Magpies nearly come undone.
A long throw found Cleworth at the back post and his flicked header was deflected onto the post and out. The resulting corner came to nothing and the points were shared.
Man of the match: Paul Mullin
He was brought in to score goals and in his first match in front of his new home fans, Mullin delivered with what could be a vital goal. Also was involved in a couple of other passages of play that resulted in chances for Wrexham.