Of course, your question is asked incorrectly. A Senator is a member of the Congress of the United States (citation: http://en.wikipedia.org/wiki/United_States_Congress). The Congress of the United States consists of the Senate and the House of Representatives. If you "think" a Senator is somehow "higher" up than a U. S. Representative, then why is the Speaker of the House 3rd in line to the Presidency? One stupid question, multiple examples of your ignorance.
As I am only interested in exposing your errors, you will have to look elsewhere to get the answer you really want. You have to ask the correct question in order to get the answer. The question you failed to ask is this: "Who was the last person whose highest office was member of the U.S. House of Representatives to be nominated by his party for President?"