The Vice President of the United States serves as president of the U.S. Senate. Vice Presidents can only cast a vote in the Senate when a tie needs to be broken. Although this doesn’t happen frequently, the Vice President does have the opportunity to influence legislation.
For example, President George Bush signed the Deficit Reduction Act of 2005 into law, with the help of Vice President Dick Cheney’s tie-breaking vote in the Senate. It was a highly contentious piece of legislation concerning the budget, which Democrats vehemently disapproved.
Vice President John Adams holds the record for the most times a Vice President was the tie-breaker in the Senate, with 29 times.