The Welshmen led from the 21st minute, Brad Walker netting from the spot after a Will Evans handball.
But the Spireites were always in the game and having knocked at the door repeatedly as the game progressed, finally made a breakthrough after the 90 minutes were up.
It stretched Martin Allen's side's unbeaten run to five games, but the wait for a home win goes on - the last one coming back in August.
Chesterfield had an early chance to test Wrexham stopper Rob Lainton, a half cleared Sam Muggleton throw crossed back into the box by the thrower, Tom Denton slicing an effort goalwards, the keeper gathering easily.
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Denton was in the thick of it a minute later, his marker Jake Lawlor going down in a heap after an aerial challenge, referee Christopher Pollard booking the Town striker.
The Spireites managed to get a man in the clear on nine minutes, but it was Denton rather than his pacier strike partner Hines and although the big frontman kept control and fed Hines inside the area, his shot was curled well over.
Wrexham, who had failed to create an opening in the first 20 minutes, took the lead shortly after when Brad Walker's ball over the top put Will Evans under pressure and referee Pollard adjudged him to have handled the ball in the area.
Walker took the spot-kick and found the net with aplomb to send the hordes of Welshmen behind the goal into raptures.
Seconds later a cross from the right found Mike Fondup, after a Haydn Hollis slip, but the frontman volleyed over.
With the visitors in the ascendancy, Callum Burton had to be at his best to palm an Akil Wright 20-yarder over the bar.
Town steadied and came close themselves before the half hour mark, Evans' rocket of a free-kick just missing on the right.
At the other end a curling free-kick to the back post was headed downwards and wide by Rekeil Pyke.
Shaun Pearson was shown the yellow for a cynical lunge that stoped Hines going clear down the right.
Chesterfield's best bit of play, in the final 10 minutes of the half, saw them switch from left to right, where Evans' cross struck an arm and went behind for a corner - the match officials unimpressed by loud penalty appeals.
It should have been 1-1 shortly after when Hines got round the back, drew Lainton and found Joe Rowley, who was off balance and could only fire over instead of into the empty net.
Both sides made a change at the break, Lee Shaw taking Evans' place for Town, James Jennings replacing Mark Carrington for the visitors.
Wright had an early chance to shoot after the break, sending a volley over the top following a smart move from a throw in.
Denton, who toiled without reward for most of the afternoon, made way for Levi Amantchi with an hour gone.
Chesterfield had a spell on top and came close once again, a corner falling to the feet of Jerome Binnom-Williams who lashed a shot at goal only for team-mate Shaw to get in the way two yards out.
With time running out Amantchi took matters into his own hands, an outrageous flick taking him away from two markers before he stung the hands of Lainton with a fierce drive from an acute angle.
Shaw earned a booking for a shove on James Jennings that sent the Wrexham man into the advertising boards and brought the two teams together for a spot of shoving.
It was Shaw who then earned a corner from which Laurence Maguire had a chance six yards out, failing to get enough contact to trouble Lainton.
The equaliser finally arrived when Maguire surprised everyone by clipping a clever ball to the back post, ignoring a clutch of team-mates in the middle and instead picking out the run of Smith, who guided a header into the far corner.
Chesterfield: Burton, Evans (Shaw 46), Muggleton (Kiwomya 76), Maguire, Hollis, Rowley, Binnom-Williams, Smith, Weston, Denton (Amantchi 59), Hines. Subs: Fortune, Reid.
Wrexham: Lainton. Roberts, Carrington (Jennings 46), Pearson, Lawlor, Young, Walker, Wright, Rutherford, Pyke (Holroyd 75), Fondup (Beavon 60). Subs: Dibble, Maguire-Drew.
Goalscorers: Smith 90; Walker 21
Yellows: Denton 4, Evans 20, Rowley 62, Shaw 81; Pearson 33, Walker 76
Referee: Christopher Pollard. Assistants: Bradley Hall, Blake Antrobus.
Attendance: 5,662 (1,520)