2016 politics: How crazy could it get?

Thanks primarily to Donald Trump, the 2016 election cycle has been full of drama so far -- but campaign season is only just beginning.

With voters set to start caucusing and casting ballots in just over a month, there are plenty of possible scenarios that could play out. Some of them, of course, are more far-fetched than others.

Here's a look at a few that may not be likely in 2016 but can't be entirely ruled out...

Hillary Clinton loses the Democratic nomination

With just a little over a month before the Iowa caucuses officially kick off the race for the White House, former Secretary of State Hillary Clinton appears well-poised to easily secure the Democratic nomination.

In a national CBS/ New York Times poll released earlier this month, Clinton continues to lead Vermont Sen. Bernie Sanders by 20 points. She leads among many voter groups - men, women, liberals, moderates, non-whites and voters over age 45. Clinton also has an edge in Iowa and a large lead in the early voting state of South Carolina, according to the CBS Battleground Tracker.

Yet in the early-voting state of New Hampshire, Clinton is 14 points behind Sanders, the Battleground Tracker shows.

And a look back at the 2008 election cycle illustrates how dramatically political fortunes can change. While then-Sen. Barack Obama managed an epic upset to secure the candidacy, his campaign didn't really pick up speed until early 2008. In early December 2007, a national CBS/ New York Times poll showed that Clinton led Obama by 17 points.

Republicans hold a brokered convention

On the Republican side of the race, billionaire Donald Trump's chances of securing the nomination seems plausible, if those willing to wait hours for his rallies can be counted on to wait in lines to vote, as well. Yet unlike their Democratic counterparts, Republicans have yet to settle on a clear second-choice candidate. Sen. Ted Cruz is currently dominating in Iowa, but in New Hampshire, he is neck-and-neck with multiple other candidates vying for second place behind Trump. There is not yet an establishment alternative.

With a dozen GOP candidates still in the race, it's not completely unthinkable that Republicans could enter their national convention in Cleveland next July with no clear-cut nominee. As CBS News' Rebecca Shabad reported, GOP officials are preparing for that possibility.

Republican National Committee Chairman Reince Priebus said on "CBS This Morning" that a brokered convention is unlikely. "I think most likely, we'll have a presumptive nominee by mid-April, end of March, but probably mid-April," he said.

Yet former George W. Bush adviser Mark McKinnon told NPR that the odds of a brokered convention are higher now with such a crowded field. "You can see a scenario where somebody wins Iowa, somebody else wins New Hampshire, somebody else could win South Carolina, and somebody else could win Florida," he said. "Let me put it this way: there's a better chance of a brokered convention than any time in our lifetime."

A third party candidate emerges

Should there be a brokered convention, it could spur Trump to run as an independent, Marc Landy, political science professor at Boston College, told CBS earlier this month. If that were to happen, Landy said, it would "kill the Republican nominee."

Trump has publicly flirted with the idea of mounting a third-party bid if he feels the Republican Party is treating him unfairly, and there's some evidence he could gain traction if he were to do so: A recent USA Today/ Suffolk poll showed that 68 percent of Trump's GOP supporters would vote for him if he ran outside the party. However, at the last GOP debate earlier this month, Trump said he "really" is ready to commit to not running as an independent. "I've gained great respect for the Republican leadership...[and] the people on the dais," he said.

Meanwhile, some Republicans are grumbling about a potential third party challenge from some other conservative, should Trump win the official GOP nomination.

Romney strategist Stu Stevens told Politico this week that if Trump won the nomination, it would spur a "very strong third-party effort," while GOP consultant Rob Stutzman also told the publication that "a third candidate would be very likely on many state ballots" in that scenario.

No candidate wins 270 electoral votes

There are 538 electoral votes available in the Electoral College, and a candidate needs at least 270 -- more than half -- to win.

If Trump or another candidate were to mount a third-party challenge, it's theoretically possible they could win some of those votes and keep any candidate from declaring victory. Yet while Trump has loyal supporters, winning any Electoral College votes as a third-party candidate would be a huge task: Even Ross Perot couldn't secure any Electoral College votes in 1992, even though he won nearly 19 percent of the popular vote.

Even without a third party candidate, it's plausible that the two major-party candidates could split the votes, at 269 each.

If no candidate wins 270, the newly-elected House of Representatives decides the president, according to the Twelfth Amendment -- each state's delegation would get to cast one vote. The Senate would choose the vice president.

Hillary Clinton keeps Obama in Washington

President Obama can't run for a third term as president, but he will no doubt remain a powerful voice in national politics. It's possible he could even stay directly involved in Washington politics and policy making. Some have speculated that Hillary Clinton, should she win the presidency, could nominate Mr. Obama to the Supreme Court.

In a wide-ranging interview with Bill Simmons for GQ magazine last month, Mr. Obama initially hesitated when asked whether he'd like to serve on the Supreme Court. Ultimately, he rejected the idea. "No--well, the reason I paused for a second was just to make sure that I let people know that I think good judges are really important, and Supreme Court justices, obviously, are hugely important," he said. "I don't have the temperament to sit in relative solitude and just opine and write from the bench. I want to be in the action a little bit more."

If Mr. Obama changed his mind, there's certainly precedent -- William Howard Taft was appointed to the Supreme Court after serving as president.

Donald Trump wins it all

There's plenty of evidence that suggests Donald Trump could never win the White House: For starters, multiple polls released in the past month have shown both Hillary Clinton and Bernie Sanders beating him in general election match-ups.

In a recent Quinnipiac poll, more than half of voters nationally said Trump doesn't have a good chance of winning, and half of all Americans said they'd be embarrassed to have Trump as their president (35 percent said they'd be embarrassed to have Clinton as their president). In a recent Washington Post/ ABC poll, as many as 69 percent of adults said they would feel anxious if Trump were president.

Meanwhile, Trump has made so many offensive remarks about women, Hispanics, Muslims and other groups that it's difficult to imagine he could pull together the diverse coalition necessary to win the general election.

All that said, Trump has defied expectations so far, building a remarkably loyal bloc of supporters. Moreover, CBS News Elections Director Anthony Salvanto reports, his suport has defied convention by cutting across demographic groups and the usual breakdowns within the GOP. Conservative voters don't seem to be put off by his controversial remarks. In fact, Salvanto noted, 74 percent of Republican voters also like the idea that Trump "says the things he says." They feel these things "need to be discussed."

Should Trump win the Republican nomination, it's possible the enthusiasm behind his campaign could carry over to the general election -- especially if outside factors, such as the economy or security issues, play into Trump's messaging.

"Nine in 10 Republicans say they feel the U.S. is becoming more dangerous and insecure," Salvanto said on "Face the Nation," referring to recent CBS polling. "That's layered on top of economic insecurity... Eight, nine of out 10 of those Republican voters say they feel the U.S. economic system doesn't help them. When you think the system doesn't work, it's not just that things are going in the wrong direction, that's when you go to a candidate who might say, 'Change the whole system. Blow it all up.'"