The constitution requires the winning candidate to obtain a majority — not merely a plurality — of electoral college votes. Because there are an even number of electors — 538 — a tie outcome of 269 for each candidate is possible. Moreover, if the pattern of the last election repeats itself, there will likely be several faithless electors, that is, those who vote for someone other than one of the major party candidates. Seven of them did so in 2016. Such an action would likewise deprive any candidate of a majority.

What happens then?

Past & Prologue

The 12th Amendment, ratified in 1804, prescribes that the incoming House of Representatives chooses a president from the top three candidates. But in a major departure from its normal procedure the same amendment requires that the House vote by state delegations, each state having only one vote. The GOP has the upper hand under this method: They control 26 states while the Democrats have 22, with four either tied or with no party in control.

It’s why President Donald Trump and Speaker Nancy Pelosi in recent days have spoken out publicly on the importance of electing members of their respective parties to the House in swing states.

That brings us to the election of a vice president. If there’s no electoral college majority, the 12th Amendment provides that the U.S. Senate makes the choice from the two leading contenders. Though Republicans now control the upper body, there’s credible speculation that they will not after the election. If that’s the case then Sen. Kamala Harris would likely win — and yes — she would be in a position to vote for herself . If the senate itself is deadlocked then the outgoing vice-president, Michael Pence, would cast the deciding vote, no doubt also voting to keep himself in office.

Though the 12th Amendment provides a method for breaking tie votes in the senate, the constitution is silent on how that happens in the House. In that instance, whoever the Senate chooses as vice president — presumably either Harris or Pence — would become the acting president.

If Something Happens to One of the Candidates After Nov. 3 and Before the Inauguration:

Just six days before the 1912 election of President Howard Taft’s vice-presidential running mate James “Sunny Jim” Sherman died.

Earlier that summer Sherman became the first sitting vice-president since 1828 to have been re-nominated for the position but on Oct. 30, 1912, less than a week before the election, the 57-year old Sherman, died of the kidney ailment then known as Brights disease.

The dilemma of designating a successor on such short notice fell to the GOP National Committee, who chose Nicholas Murray Butler, then the president of Columbia University. His many educational reforms as leader of what was then the largest intuition of higher learning in the world, had made him a respected figure among Republican leaders.

When party leaders asked Butler if he would accept the nomination he asked, “Do we have a chance?”

The reply, “No.”

Butler‘s rejoinder: “Good, then I’ll take it.”

Icon that he was in his own right it’s understandable why he would have wanted to be assured that he would have no chance of being required to vacate the pinnacle of one of the world’s leading universities if he accepted a vice presidential nomination. The White House itself, however, might have been another matter as the man who took over the helm of the university after Butler retired, Gen. Dwight D. Eisenhower did find the nation’s top office sufficiently alluring to leave the same job which Butler had once been so unwilling to relinquish.

Though the Taft-Butler ticket went down to defeat, placing third behind Teddy Roosevelt and Woodrow Wilson, the episode of having to abruptly replace the nominee on a major party ticket illustrates the type of challenge that one day the country might be called upon to address. Such a prospect has been brought home this year due to the age of both major party nominees, Former Vice President Joe Biden turning 78 in November and Trump having turned 74 in June. Though they are not the oldest to have ever run on a major national party ticket — that honor belonging to Henry Davis who was just a month shy of his 81st birthday when he was the Democratic nominee for vice president in 1904 — they are the oldest major party nominees for president in either party. (President Ronald Reagan was 73 when re-nominated in 1984 even though he was 77 by the time he left office in 1989.)

A vacancy in one of the major party positions also occurred before the 1972 election. That’s when in August of that year the Democratic National Committee substituted former Peace Corps Director and Kennedy in-law R. Sargent Shriver for Senator Thomas Eagleton as Senator George McGovern’s running mate.

What happens if one of the nominees dies or resigns after the November election and before the January 20th inauguration date?

The answer is relatively straightforward if the vacancy occurs before members of the electoral college meet December 14th In that period of time the national committee of the party involved would designate a successor, just as it did in both the Sherman/Butler and the Eagleton/Shriver cases. (Indeed, in the 1912 situation Sherman’s death occurred so close before the election that the committee did not meet to nominate Butler until after the November vote, though it was well before the electoral college met a month later.)

For much of our nation’s history there was no satisfactory answer to the question of what would occur if a nominee died after the electoral college met in mid-December and before the inauguration. A reasonably clear answer was put forth on ratification of the 20th amendment in 1933, however. It states that “If, at the time fixed for the beginning of the term of the President the President shall have died, the Vice President Elect shall become President…”

A law enacted under this amendment also provides that should the Vice-President elect’s position be vacant in this interim period that the Speaker of the House would acceded to the office. Should Kamala Harris be elected, for example, but become improvidently unavailable, then the next U.S. House Speaker, likely Nancy Pelosi, would fill her shoes.

So, as if the spectacle of the first presidential debate were not enough it’s intriguing to contemplate what might also happen even after Nov. 3 in the unfolding odyssey of the way our system sets the course for what follows.

Paul Mills is a Farmington attorney well known for his analyses and historical understanding of public affairs in Maine. He can be reached at pmills@myfairpoint.net.