The disclosure provides polymers having antimicrobial activity and articles with the polymers coated thereon. The polymers include a first pendant group comprising a first cationic component, a second pendant group comprising a nonpolar component, and a third pendant group comprising an organosilane component. The disclosure also includes methods of coating medical device articles and body fluid-receiving substrates with the antimicrobial polymers. The methods further include the use of adhesion-promoting components.