The Rockets trailed by 11 at halftime, but outscored the Bucks over the final two periods 68-43.
Harden reached the 20-point mark for the 15th straight game, scoring 29 and dishing out seven assists. He came into the contest as the NBA's fifth leading scorer. Harden hit 11-of-18 shots from the field and produced 16 of his points during the big second half.
Houston hit 53 percent from the field while taking 83 shots, 33 of which were from beyond the arc. The Rockets made 13 of those long-range efforts.
Houston has won three straight and the Bucks have lost three in a row.
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