How can Congress override a presidential veto?

To override a presidential veto, Congress must achieve a two-thirds majority vote in both the House of Representatives and the Senate. This requirement is established by Article I, Section 7 of the U.S. Constitution, which specifies that after a bill is vetoed by the President, Congress can reconsider it. If two-thirds of both chambers agree to pass the bill again, it effectively negates the President's veto and allows the legislation to become law.

The two-thirds majority is intended to ensure that there is substantial agreement among elected representatives before overriding the President's decision, reflecting a significant consensus in the legislative branch. This high threshold underscores the balance of power between the legislative and executive branches, ensuring that both have a voice in the law-making process.

Achieving a simple majority would not suffice for an override, as this would only reflect a bare minimum of support and not the strong consensus required to counteract the President's veto. Unanimous consent and a three-fourths majority are not valid methods for overriding a veto according to constitutional provisions, thus further solidifying the necessity of a two-thirds majority in both houses.