The President of the United States is undoubtedly the most powerful person in the White House. But, the President is not the only one with power in the nation's capital. The Vice President, the Speaker of the House, and the Senate Majority Leader all have a significant amount of power, too.

The President

The President is the head of state, the chief executive, and the commander-in-chief of the armed forces. The President has the power to sign or veto legislation, make executive appointments, and grant pardons. The President is also the face of the United States to the world.

The Vice President

The Vice President is the second-in-command of the United States. The Vice President is first in the line of succession if the President is unable to serve. The Vice President also presides over the Senate and can cast a tie-breaking vote.

The Speaker of the House

The Speaker of the House is the leader of the House's majority party. The Speaker is in charge of presiding over House debates and naming committee chairs. The Speaker comes after the Vice President in the line of succession.

The Senate Majority Leader

The Senate Majority Leader is the leader of the majority party in the Senate. The Majority Leader sets the Senate's agenda and controls which bills are brought to a vote. The Majority Leader is also responsible for negotiating with the Minority Leader on behalf of the Senate.

The National Security Advisor is responsible for advising the President on national security matters. They are a key member of the President's national security team and are often involved in major decisions. 

The White House Counsel is the President's chief legal advisor. They are responsible for advising the President on legal matters and are often involved in major decisions. 

So, who has the most power in the White House? It's hard to say. each of these individuals has a lot of influence and authority.