Following Bernie Sanders's victory in New Hampshire, supporters are optimistic that the 'Bern' will gain momentum and spread to South Carolina and Nevada next. They also couldn't help but dance throughout the rally, going as far as dedicating some serious dance moves to the senator. (Alice Li/The Washington Post)

Two entirely outside-the-mainstream candidates won their respective presidential primaries in New Hampshire.

It did not take long for the networks to call the race for Sen. Bernie Sanders (I-Vt.) in a monster win over Hillary Clinton in the Granite State’s Democratic primary. Clinton, who months ago was deemed inevitable, now has essentially one tie and one horrible loss. Her campaign is expected to undergo a shake-up, but real questions remain about whether any fix, other than a new candidate, will spare the Democrats from nominating an avowed socialist. Vice President Biden’s phone lines will be burning up for the next few days.

Over on the GOP side, the reality of the Donald Trump phenomenon hit home with his first win. His coalition is unusual — independents, moderates, anti-immigrant zealots and older voters. Whether it has staying power beyond a small state will be hashed out in the weeks ahead. He, however, will not be going away anytime soon. While his ceiling may be about 30 percent, the more traditional candidates will need to fight Trump not with conservative bromides but with bare-knuckle fighting and empathy for the working-class voters Trump attracts.

Republican presidential candidate Donald Trump addresses ecstatic supporters following his win in the New Hampshire primary. (Reuters)

As of this hour, behind Trump in the GOP field is a muddle, which may turn out to be a blessing for Jeb Bush (who is now on par with some of the top finishers in Iowa) and Sen. Marco Rubio (Fla.), who may have been bruised in the last debate but was far from mortally wounded. Ironically, the overbearing attacker, New Jersey Gov. Chris Christie, seems destined to finish in single digits, and likely will be left off the debate stage Saturday. His run, one has to imagine, is nearly done.

The calls for Bush to get out of the race will cease, and he will find renewed support among party insiders, who may see him as one of only a few viable options to Trump and Cruz. For Cruz, the nightmare is coming true: Trump remains and has captured the anti-establishment zeitgeist in the party. With little appeal outside his very conservative base, Cruz finds himself squeezed on both sides. Finishing behind Bush would certainly be a blow to his fundraising prospects and put a halt to any momentum coming out of Iowa. A better showing in South Carolina will be essential.

If Kasich holds on for second, in part due to his strong showing with independents, he will need to prove he is not too liberal for the party. His national organization is a question mark, although nothing draws money and staff like success.

And finally there is Rubio, who is where Bush was a few weeks ago — down but not out. He now has had his wake-up call, not unlike George W. Bush in 2000, who got whipped in New Hampshire and had to come back in South Carolina. Rubio will need to show strength quickly or face calls — in a total about-face — for him to cede ground to more electable center-right contender.

In short, Clinton is in deep trouble, Trump is not going away, and the GOP alternative to Trump is far from clear.