to speak eagerly about something that you support.
Once again she was banging the drum for pre-school nurseries.
(often + for)
The opposition parties are always beating the environmental drum.
bang the drum
To voice one's support for something. Quit banging the drum for that candidate—he is simply not qualified for the job.
bang the drum
or
beat the drum
If you bang the drum or beat the drum for something or someone, you support them strongly and publicly. The trade secretary promised to `bang the drum for industry'.If the French want to beat the drum on behalf of French culture, good luck to them.
bang/beat the ˈdrum (for somebody/something)
(especially British English) speak with enthusiasm in support of somebody/something: She’s really banging the drum for the new system.