Wotton's 25-yard free-kick two minutes after half-time took his goal total to three in the last two matches to continue the Pilgrims' steady climb away from trouble with four wins and three draws from their last eight league matches.
Leicester, on the other hand, crashed to their sixth league defeat in a row and have just one victory to their name in their last 11 matches, against Tottenham in the FA Cup.
In truth, Foxes goalkeeper Rab Douglas' heroics kept the margin of victory down in a match which was being replayed after the original date - on November 1 – had been abandoned because of a waterlogged pitch.
Douglas was, however, powerless to prevent the Plymouth captain from securing a victory which left Leicester in the relegation zone and nine points adrift of Argyle.
Mickey Evans won a free-kick from centre-back Patrick Kisnorbo and his skipper did the rest in the 47th minute by smacking the ball over the defensive wall and past a helpless Douglas.
Leicester had not mustered a single shot on the home goal in the first 45 minutes as Douglas denied David Norris, Nick Chadwick and Wotton is quick succession.
A double stop from Norris and Chadwick's attempted follow-up was particularly impressive, and another backward stretching effort tipped over Wotton's looping header.
Leicester were much more adventurous after conceding, although they were fortunate to survive two penalty claims when Chadwick was fouled and when Patrick McCarthy appeared to have handled.
However, centre-back Elliott Ward, an outstanding man of the match, was solid in the heart of Argyle's defence as Leicester pounded the Plymouth back line in search of an equaliser.