In case of a tie in the electoral return, the chooses the president, with each state having
vote(s).

If there is a tie the president and vice president are chosen by contingent election. In this a vote of the united states House of Representatives decides the president  while the Senate decides the contingent election for the vice president. Contingent election procedure was decided by Article Two, Section 1, Clause 3 of the U. S constitution, it was modified in 1804 by the 12 th amendment.

Contingent elections have occurred only three times in US history during early 1800s.