How many U.S. senators are there?

Why this is the answer

There are 100 senators, and the number comes from simple multiplication: the Constitution gives every state two seats, and there are 50 states. Size and population do not change it. California, the state with the most people, and Wyoming, the state with the fewest, each have two. Every senator also gets one vote, so in the Senate a small state carries exactly the same weight as a large one. The 2008 civics lessons put it plainly: all states have equal power in that chamber. Because the number is tied to the states, it would change only if the number of states changed. Each senator serves a six-year term and represents all the people of the state, not a single district, so the Senate is the smaller chamber in members while each of its members speaks for a whole state. The framers also wanted the Senate to stay small, so it would be more orderly than the much larger House. The same lessons quote James Madison in Federalist No. 63, who described the Senate as a temperate and respectable body of citizens that works in a cool and deliberate way. The number matters in practice too. Most bills need 51 votes to pass the Senate, or a majority of the senators present and voting. When the senators split evenly, the Vice President, who serves as President of the Senate, can cast the deciding vote; otherwise the Vice President has no vote there at all. The answer USCIS lists is one hundred. The mistake to avoid is mixing up the two chambers. Applicants sometimes say 435, which is the number of voting members in the House. Another slip is answering 50, from a picture of one senator per state. If you remember that each state sends two, the rest is arithmetic: two times 50 is 100.