"To command a majority" means having enough support or votes from a majority of people in a group or organization to have control or power over decision-making. Full definition
Being an entrepreneur and starting a business will command the majority of your time — you have to be prepared to eat, sleep and breathe your business. (entrepreneur.com)
A prime minister can't govern if he or she can't command a majority. (labour-uncut.co.uk)
Common Core still commands a majority among the population as a whole. (educationnext.org)