who selects the president when no candidate receives a majority of electoral votes
Electoral College (United States) If no candidate for president receives a majority of electoral votes for president, the Twelfth Amendment provides that the House of Representatives will select the president, with each of the fifty state delegations casting one vote. If no candidate for vice president receives a majority of electoral votes for vice president, then the Senate will select the vice president, with each of the 100 senators having one vote.[14][15]
President-elect of the United States No constitutional provision or federal law requires electors to vote according to the results of their state's popular vote, though some states bind their electors to their pledges by state law. Historically, there have been only a few instances of "faithless electors" casting their ballots for a candidate to whom they were not pledged, and such instances have never resulted in changing the final outcome of a presidential election. The popular vote does not declare the presidency but the Electoral College vote does. Even if the popular vote goes to one candidate, another may win the electoral vote and the presidency, as has happened in 1876, 1888, 2000 and 2016.
Twenty-fifth Amendment to the United States Constitution Section 2. Whenever there is a vacancy in the office of the Vice President, the President shall nominate a Vice President who shall take office upon confirmation by a majority vote of both Houses of Congress.
Electoral College (United States) Candidates for elector are nominated by state chapters of nationally oriented political parties in the months prior to Election Day. In some states, the electors are nominated by voters in primaries, the same way other presidential candidates are nominated. In some states, such as Oklahoma, Virginia and North Carolina, electors are nominated in party conventions. In Pennsylvania, the campaign committee of each candidate names their respective electoral college candidates (an attempt to discourage faithless electors). Varying by state, electors may also be elected by state legislatures, or appointed by the parties themselves.[48]