The correct answer is two-thirds supermajority votes or convention called by Congress on application of two thirds
The presidents may incorporate into the Executive's budget projects desired by congressmen or, with punishment, exclude from the budget such projects. Popular presidents can help congressmen in their election campaigns. The second brake is the President's specific constitutional power over Congress: the veto. The President may, by veto, reject any project approved by the Congress. A 2/3 majority is required, in each case, to overturn a veto. It is such an occasional majority that the simple veto threat is often enough to persuade Congress at the time of vote.