Dempsey denies United at the death
Van Persie had put Manchester United on course for a vital win when he scored his sixth goal against Spurs, but after a sustained period of pressure, Dempsey delivered Andre Villas-Boas' men a thrilling equaliser with less than 60 seconds of the match remaining.
The American, who had missed a gilt-edged chance earlier in the second half, got on the end of Aaron Lennon's pull-back and slotted home after David De Gea had gone walkabout. The draw means United are now just five points ahead of Manchester City after Roberto Mancini's men after their win over Fulham yesterday.
For so long this seemed like it was going to be one of the disciplined no-frills victories that have been so key to helping Sir Alex Ferguson win his 12 titles. Van Persie, who was making his first appearance in north London since his summer switch from Arsenal, took advantage of some sloppy marking from Kyle Walker to nod home a 25th-minute opener, and the away side looked comfortable thereafter.
Villas-Boas had challenged his men to prove they were serious top-four contenders by beating their esteemed visitors, and for the majority of the match they failed to deliver. Their passing was often poor while Jermain Defoe and Dempsey both missed good opportunities, yet that counted for nothing come the final whistle after the heart-stopping equaliser went in.
Despite heavy snowfall in the capital overnight, the game went ahead after a late pitch inspection. Tottenham settled the better of the two sides, getting into their rhythm on what was a bitterly cold afternoon in the capital.
Lennon drove low at De Gea, who palmed it into Defoe's path, but the England striker was ruled offside. Spurs' fans remained upbeat despite the freezing conditions, but the atmosphere soon turned sour when United took the lead.
Van Persie strikes first
Danny Welbeck found Tom Cleverley and he whipped in a perfect cross for Van Persie, who lost Walker and nodded past Lloris. The hosts almost hit straight back through Defoe, who stung De Gea's palms with a powerful drive.
Tottenham lacked ideas going forward and the home crowd started to turn on their team. They upped their game just before half-time, though. Bale thundered a powerful volley which De Gea did well to save just before half-time and Lennon was denied a run at goal when he was hacked down by Patrice Evra.
Spurs flew out of the blocks after the re-start. Defoe drifted in from the right flank and shot just wide of De Gea's goal and Bale curled an audacious shot just over. Dempsey should have equalised in the 52nd minute when he picked up Mousa Dembele's pass following a mazy run by the Belgian, but De Gea saved with his legs.
Defoe managed to wriggle into the box and his blocked shot fell to Dempsey but he shot wide. Walker sped down the right and delivered a wicked cross for Caulker, but he again could only steer his effort wide of goal.
Bale looked the most likely to break the United defence. The Welshman used his pace to create some space for Defoe, but he took one touch too many and Nemanja Vidic stole in. A powerful shot from Bale clipped Ferdinand and sailed inches wide as Tottenham's bid for a point looked like ending in failure.
Yet with two minutes and four seconds of the three added minutes gone, Dempsey popped up in the box and stabbed home after De Gea had flapped at a cross.