Here are 6 plausible ways this election could go wildly off the rails

Odds are, Tuesday's presidential election will ultimately prove boring. Millions will cast votes for Hillary Clinton or Donald Trump. One candidate will win, the other will lose, and that will be that.

But given the closeness in the polls, there's at least a chance the final results could be much, much messier. Like: an Electoral College tie that has to get resolved by Congress. A disputed state. A pivotal elector going rogue. Chaos on the level of Bush versus Gore in 2000 or Tilden versus Hayes in 1876.* Thanks to our byzantine Electoral College system, all sorts of convoluted outcomes can happen, at least in principle.

So here's a guide to six wildest ways this election could end. None of these are very likely, mind you, but they're all unnervingly plausible.

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Keep in mind a key fact about US presidential elections: Voters don't directly decide who becomes president. Instead, voters in each state vote for specific slates of "electors" who, in turn, convene in December to select the next president.

The vast majority of the time, these electors vote for the candidates they've previously pledged to support. So if a majority of voters in New York elect the Democratic slate of electors, those electors will almost certainly cast their 29 electoral votes for Clinton. In about half the states, electors are bound by law to keep these pledges.

But electors don't absolutely have to follow through. If an elector wants to go rogue and vote for a different presidential candidate, there's really nothing stopping him or her. And in a close race, like the scenario shown on the map above, a couple of "faithless" electors could conceivably swing the entire election.

So consider: Right now, in Washington state, two electors on the Democratic slate have suggested that they won't vote for Clinton. Here's Robert Satiacum, a Democratic elector and a former Bernie Sanders supporter: "No, no, no on Hillary. Absolutely not. No way." A second elector, Bret Chiafalo, has also refused to say he'd back her. Under state law, they'd face criminal charges and a $1,000 fine for defying the state's election results, but they could do it.

If Clinton only won states worth 270 electoral votes, those two rogue electors could potentially tip the race to Trump. If they voted for Sanders, the final tally would be 268-268, and the race would get thrown to the GOP-controlled House (see below). True, in that situation, as Jeff Stein explained here, these Democratic electors would face enormous pressure from the rest of the party to cast a vote for Clinton. And it seems awfully unlikely that two progressive electors would hand the White House to Trump out of spite. But thanks to the Electoral College, this is all totally possible.

Under the Electoral College, a candidate needs 270 out of 538 available electoral votes to become president. But the situation gets more complicated if neither candidate gets to 270. Which can definitely happen — just see the not-implausible electoral map above, where Trump wins Nevada, New Hampshire, North Carolina, and Florida.

So what happens in the event of a tie? Well, assuming that the electors all voted as expected and certify the 269-269 vote, the presidential election would get thrown to … the House of Representatives.

On January 6, 2017, the newly elected House members would gather in Washington, DC, to select the next president. Each of the 50 state delegations would get one vote, and the delegations would have to choose among the top three electoral vote-getters. Whichever candidate gets the support of 26 state delegations becomes president.

There's a good chance that at least 27 state delegations will be majority Republican come January (especially if the presidential race is so close). So the most likely scenario here is that they'd cast a vote for Donald Trump and he would become president of the United States. It'd be contentious as hell, but it would be perfectly constitutional: it worked for Thomas Jefferson and John Quincy Adams, after all.

The House wouldn't have to give the election to Trump, however. The only rule, under the 12th Amendment, is that the state delegations have to vote for one of the top three finalists in the Electoral College.

Enter Evan McMullin. The 40-year-old former CIA officer is independently running for president, backed by a few establishment #NeverTrump types like Bill Kristol. And he's doing remarkably well in Mormon Utah, well enough that he could conceivably win the state and be a top three finalist in the Electoral College.

In that case, 26 Republican state delegations could in theory decide that they'd prefer an establishment guy over Trump and make McMullin president — even though he'd only won one state. It seems hard to fathom the House GOP would ever do this, since it'd make millions of Trump voters in their districts absolutely livid. But rules are rules, and this one can't be ruled out.

There's one other important detail about a tie in the Electoral College. The House gets to choose the president. But the Senate gets to choose the vice president — with each senator getting one vote and being required to pick among the top two vice presidential vote-getters in the Electoral College.

It's entirely plausible that come January 6, 2017, Democrats will have a thin majority in the Senate. So, yes, they could select Tim Kaine to serve alongside newly installed President Donald Trump. I'll just leave that possibility here.

In the election scenario seen above, the race all comes down to New Hampshire. Whoever wins New Hampshire gets 270 electoral votes and goes on to the White House.

So let's imagine New Hampshire is … tied. Literally tied. As in: 360,212 people voted for Trump; 360,212 people voted for Clinton.

What happens in that case? Most states have their own laws for what to do in the event of a tie. Some, like North Carolina, just redo the election. But others, like New Hampshire, decide the winner by "lot." As in, a coin toss or drawing straws. In the past, New Hampshire's secretary of state has broken tie votes at the local level by gathering the two candidates, placing two numbered balls in a jug, shaking the jug, and then asking one of the candidates to call out a number, before picking out a ball.

The statistical odds of a tiebreaker in New Hampshire determining the election are spectacularly low. But sure: President Trump, brought to you by two balls in a jug. That's a thing that could happen.

If you consult your repressed memories, you may recall that the 2000 presidential election all came down to disputed vote counts in Florida. There were hanging chads. Al Gore wanted manual recounts. And, after weeks of disorder, the Supreme Court eventually resolved these questions in favor of George W. Bush, by a 5-4 vote that still triggers deep loathing to this day. It was bitter, it was divisive, it was not something anyone really wants to repeat again.

Here's the bad news: if a similar dispute in Florida happened today, it would be so, so much worse. Because right now, the Supreme Court only has eight members — four liberals and four conservatives — thanks to Senate Republicans' refusal to confirm Merrick Garland. Which means that we could easily see the current Supreme Court reach a 4-4 deadlock over some crucial recount questions.

If that happened, any electoral disputes would ultimately get resolved by lower circuit courts or state supreme courts, depending on where the disputed elections occurred. As Darren Samuelsohn and Josh Gerstein explain for Politico, each of these courts has its own particular partisan bent, and litigants on both sides would try to steer any case toward a venue more favorable to their party.

It'd be the election that never ended. The legal wrangling and ensuing political circus would drag on for weeks. Eventually, some court somewhere would make a final decision. But it'd get incredibly ugly.

I mentioned above that we could see chaos along the lines of the Samuel Tilden versus Rutherford B. Hayes election of 1876. On second thought, scratch that. That 1876 election was just far crazier (and far more appalling) than anything conceivable today.

In 1876, you had Southern states still under armed occupation post-Civil War. You had violent attacks by whites against would-be black voters. Three states — Florida, South Carolina, and Louisiana — couldn't even agree on which candidate had won. A 15-person electoral commission split between the two parties in which the 15th appointee, a Supreme Court justice with a reputation for independence, just happened to get offered a Senate seat by Republicans in his home state, thereby giving the final tie-breaking seat to the GOP. In the end, the Republican Hayes won the White House, but only after agreeing to withdraw the remaining federal troops from the South and put an end to Reconstruction — which was followed by decades of black disenfranchisement throughout the South.

Nothing this year really comes close.