Each state gets 3 votes. One for each state in the House and each Senator.
The contingent election procedure, along with the other parts of the presidential election process, was first established in Article Two, Section 1, Clause 3 of the United States Constitution, and then modified by the 12th Amendment in 1804. During a contingent election, each House state delegation casts one en bloc vote to determine the president, rather than a vote for each representative. Senators instead cast votes individually for vice president.
Each state gets 3 votes. One for each state in the House and each Senator.