Is the speaker of the house the most powerful officer in congress?
In general, yes, this is one of the most powerful posts in Congress. However, the majority leader of the Senate is quite powerful as well–and in some ways is more powerful. For instance, the speaker of the House has to be reelected every two years, whereas the Senate majority leader is reelected only every six years has more control over judicial and other presidential appointment. Certainly both posts are powerful.