throw your weight behind someone
throw (one's) weight behind (someone or something)
To wield one's influence or power to support or promote someone or something. The small-town candidate is hoping the senator throws his weight behind him in the race. If we can get a corporation to throw its weight behind our charity campaign, we can raise even more money.
throw your weight behind someoneuse your influence to help support someone. informal
2000 South African Times U.K. Tony Blair and…Bill Clinton have thrown their weight behind a South African-engineered ‘Marshall Plan’ to rescue the developing world from deepening poverty.