Final answer:
To override a presidential veto, Congress needs a two-thirds majority vote in both chambers.
Step-by-step explanation:
In order to override a presidential veto, Congress must approve the bill again by a two-thirds vote in both chambers. This means that a supermajority of members in both the House of Representatives and the Senate must vote in favor of the bill. Once the bill receives this level of support, it becomes law despite the president's objections.
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