A length-adjustable support having a telescopic column assembly that includes a rotatable spindle rod configured to telescope an interior tube into and out of an exterior tube, or vice versa, of the telescopic column assembly in order to adjust the length of the length-adjustable support. The column assembly is illustratively attached to a motor housing containing a motor that rotates the spindle rod. In illustrative embodiments, a portion of the spindle rod is attached to the motor housing via a bushing member comprising two complimentary bushing components that surround the spindle rod and support a spindle plate that mates with the spindle rod to rotate therewith. The motor assembly is configured to substantially float within the motor housing and is attached to a flange of the housing by a clip or grommet that retains an attachment arm of the motor assembly.