The 24-year-old Slovenian, who joined Newcastle in 2009, helped Wigan win the League One title last season and will now hope to be involved in another promotion from the same division with the Bantams.
Their manager is Stuart McCall, who was in charge of Rangers when Vuckic had a successful loan spell at Ibrox in 2015.
As well as the Gers and Wigan, Vuckic has also spent time on loan with Rotherham and Cardiff. He’s made a total of 18 appearances for Newcastle, scoring one goal, but hasn’t played a senior competitive game for the Magpies since a 1-0 FA Cup third round defeat at Leicester in January 2015.
However, he scored twice for United’s under-23s in their opening Premier League 2 Division Two match of the season against Norwich.