The United States currently employs a majority voting system for its legislative branch, For the House of Representatives elections, the candidate with the most votes in each of the 435 congressional districts wins a seat. For the Senate elections, the candidate with the most votes in the entire state wins a seat.
In a lottery voting system, winners would be chosen randomly, but candidates with more votes would have a better chance of winning. Only candidates who get at least 5% of the vote can be in the lottery.
For example, if Candidate A gets 200 votes, Candidate B gets 800 votes, and Candidate C gets 5 votes, then only A and B qualify. A would have a 20%chance of winning while B will have a 80% chance of winning.