Carlisle enjoyed most of the possession and created a host of good chances but it was another frustrating afternoon at Brunton Park as Cambridge pounced on one lapse of concentration to take a share of the spoils.
United started well with a free kick from Grainger which saw Bennett tumble to the floor as he came under pressure inside the area. Devitt was onto the second ball as it bobbled his way and his exchange with Grainger brought a corner as the left back's low delivery was hooked behind.
Devitt sent his corner deep and Hill was on hand to nod it back into the mix. Striker Richie Bennett did well to stand his ground, and his nodded touch set the ball nicely for Hope to volley. He claimed a pull as he was dragged to the floor and Forde raced off his line to scoop up the bouncing ball.
The Blues came again down the left flank when Grainger picked out Hope on the edge of the box. A flick from him released Devitt, but he was at a tight angle and his crisp volley was easy for Forde to gather.
Another Devitt corner had the Cambridge back line stretched as Forde came out to challenge with Bennett. His misjudged punch was chested down by the set piece taker but he had to rush his volley and it whistled over the target.
A lovely United move on 16 minutes brought a round of applause from the crowd as Liddle passed the ball out of defence as he used the space in front of him. Nadesan protected it, before rolling it into the penalty area, and Liddle came bursting through having continued his run. He was thwarted by a last-ditch tackle which eventually forced the ball behind for a goal kick.
Devitt had his corner bearings bang on once again when he rattled his delivery at the penalty spot. It had Ellis interested as he came through bodies, but his header was smothered by a lunge from Taylor. Hope stayed wide and it was quickly fed to him as he cut inside his man. He spotted Nadesan on the move but a flicked header from a whipped pass dropped just the wrong side of the upright.
Carlisle thought they'd scored on 36 minutes when Grainger found the perfect free kick delivery from wide on the left. Bennett connected with a firm volley from just eight yards out but Forde somehow got down to his right to make a fantastic save.
It was all about the home side and Joyce was next to test Forde when a punch from a Devitt cross came his way. He spotted the keeper off his line but his attempt at a lob hung in the air a moment too long and the stopper scampered back to grab it from beneath his bar.
United took the lead their first half play had deserved two minutes into the second period when Grainger shielded the ball before bringing Devitt into play. His excellent cross was met by Ellis on the back stick and his touch put it on a plate for Richie Bennett to sweep home his eighth of the campaign from very close range.
It was a short-lived lead though as the first purposeful attack of the day from Cambridge brought them back to level terms. Brown crossed, Ibehre nodded it down, and George Maris did the rest with a header which looped over Bonham and into the net.
The game opened up and Joyce had a drive blocked at one end, with the same happening to Brown at the other, and Bennett almost found himself clean through as he raced after a ball over the top. Taylor did just enough to shepherd it back to his keeper.
A piledriver from Liddle brought a chorus of 'oohs' from the crowd as he connected well with a half-cleared corner. Forde was on the dive but he wasn't to be needed as a touch from Deegan was enough to put it behind to safety.
Devitt glanced a decent header onto the roof of the net, and Clint Hill was next in the queue for a pop at the target when the ball fell kindly for him inside the area. He opted for power but he sent his toe poke over the bar as he tried to find the roof of the net.
United had a golden chance to get themselves back in front with just ten minutes left to play when Grainger picked out Ellis with another superbly flighted free kick. The big defender got plenty on his header but it was just too high and it whisked over the bar. The same player had a second similar effort deflected over the bar moments later, but was frustrated to see that the officials had missed the defensive touch.
Forde dived low to save expertly from Devitt late in the day, when the wide man beat his man and went for the bottom corner, and the keeper was the hero of the hour again when he arrived late to tip a good volley from Ellis past the post.
Late half chances went begging and United had to settle for the point from a game in which they had been well on top.
Carlisle United - Bennett (47)
Cambridge United - Maris (50)
Cambridge United - Brown (52), Deegan (77)
Carlisle United - Bonham, Liddle, Ellis, Hill, Grainger, Devitt, Jones, Joyce, Hope (Stockton 77), Nadesan, Bennett. Subs - Gray, Parkes, Nabi, Brown, O'Sullivan, Egan.
Cambridge United - Forde, Halliday, Deegan, Taylor, Ikpeazu (Waters 90), Dunk, Taft, Ibehre, O'Neil (Amoo 73), Maris (Lewis 82), Brown. Subs - Mitov, Carroll, Legge, Phillips.
Referee - Richard Clark
Attendance - 4,652 (185 away fans)