Last week, Ted Cruz made one of the biggest decisions of his political career: To essentially hand the 2016 Republican nomination to his rival, Donald Trump.

This week, the Texas senator returns to his day job on Capitol Hill facing a decision that carries perhaps just as much weight: whether to continue being an obstructor to official Washington or to try to work within official Washington.

What tack Cruz decides to take could shape his political future. There are political benefits to Cruz if he doubles down on the brand that Washington loves to hate, and there are plenty of benefits to him if he makes friends in this town after the failure of a presidential campaign without them.

Cruz's reputation, after all, is what brought him to the dance. But his lack of likability wound up hurting him toward the end.

On Tuesday, his first full day back in the Senate, he gave no indication to reporters he was drastically changing his strategy. "I look forward to pressing in the Senate the very same things I was pressing for on the campaign trail," he said.

Cruz is a politician who is likely weighing the pros and cons. So let's do the same, and game out how it could benefit Cruz politically to stay the obstructor-in-chief or to change his tune now that he's arguably next-in-line for the GOP presidential nomination in 2020 (or beyond).

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As we -- and numerous other journalists -- have detailed this election cycle, Cruz came to Washington four years ago with seemingly one mission: to wreak havoc.

Perhaps he foresaw this outsider-appeal wave on the horizon, making its way toward us and crashing into the shore of American politics by the time he was ready to run for president. Perhaps he simply thought Washington works all wrong and the only way to fix it was by throwing the political equivalent of a bomb at it.

But whatever the reason, Cruz clearly thought it was important. He committed himself to the strategy 110 percent (you don't call Senate Majority Leader Mitch McConnell a "liar" on the Senate floor without conviction), and now it's part of who he is.

Washington is built on reputations. And Cruz carefully spent years building his into a national brand. To start from zero would leave Cruz with very little political capital in this town - not to mention risk making him look like a chameleon with no true convictions.

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Washington is built on reputations for a reason. Politicians want to work with people they like, or at the very least, people they can trust.

Cruz -- as he is now -- is not that guy. He is arguably the most reviled man in Washington, or at least he was before Trump. Republicans have called him a "jackass" and "Lucifer in the flesh" -- and that's just one (mouthy) guy --and have mused that he could be murdered on the Senate floor and nobody would be convicted.

What's perhaps more damaging for Cruz's relationships is that many Senate Republicans feel as if they can't trust him. Cruz has been known to pull a parliamentary stunt and stop up the whole Senate without any warning to his colleagues, even when explicitly offered the chance to give them a heads up.

One frustrating Friday night in 2014, the entire Senate had to turn around on their way home because Cruz decided to surprise them by taking one of his short-lived stands. And that's another habit of Cruz's that really ticks off senators: He's often the only person to benefit from his dramatic, time-consuming and sometimes politically costly maneuvers.

Cruz may indeed harbor visions of a 2020 run. But he's got some time on his hands, so he might find he actually wants to do work in the Senate and prove he can work with colleagues in a presidential way.

Cruz does seem to have a diverse array of interests. Like, did you know he's actually championed two bills President Obama has signed into law?

One law denies visas to "known terrorists" from serving as ambassadors to the United Nations, which is headquartered in New York. Another law gives private companies ownership over what they mine on asteroids in space, an attempt to push government-funded space travel to the private sector.

As of right now, there are very few people who want to work with him on much of anything. It's in Cruz's power to change that and grow as a politician.

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Cruz can still capitalize on the reputation he's built, even if it didn't work out for him the way he had hoped.

He could be the next Jim DeMint, writes conservative blogger Erick Erickson. Like the former South Carolina senator who now heads a conservative think tank, Cruz could recruit, fund and help train tea party candidates to join him in the Senate, furthering the grassroots conservative cause he hopes to lead.

And it's not like with Cruz's exit in the presidential race, the establishment vs. insurgent battle in the GOP has dissipated. It's still raging, and Cruz has an opportunity to be a key figure in it.

What's more, 2016 proved that outsiders reign in today's GOP; there just happened to be two of them facing off at the end of the campaign.

To give up now would be to admit defeat, Erickson writes: "If he breaks, he will truly have lost. He should note that every attack made on the campaign trail to undermine him involved those times he tried to work with his own party's leadership."

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It's no secret that Cruz traveled the nation running for president bragging not about what he's done, but what he's tried to stop: Obama's health-care law. Obama's immigration actions. The Export-Import Bank. But toward the end of his campaign, Cruz offered a suspiciously convenient olive branch to Congress:

We -- and the rest of Washington -- were understandably skeptical.

There were pretty clear political benefits to Cruz saying this. By some fluke of the universe, he had become the establishment candidate in the race and would need the establishment's backing to stop Trump. Time to start playing nice, right?

We don't expect Cruz to launch another presidential bid on his bipartisan record, but he may want to keep that campaign promise in his back pocket for the next time he needs to the establishment to come to his rescue. Extending an actual olive branch even a little bit would go a long way. At the end of 2015, Cruz was ranked one of the least bipartisan senators in recent decades by the nonpartisan Lugar Center and Georgetown University's McCourt School of Public Policy.

He has some room to grow without damaging his established reputation. But as we all learned in first grade, actions speak louder than words.

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Imagine it's Nov. 9, 2016, the day after Election Day. Trump just got creamed by President-elect Hillary Clinton. And Republicans blame themselves for not nominating a true conservative.

In that all-too-real possibility, it's easy to see an opening for a guy like Cruz -- who has impressively wielded parliamentary tools and committed to bold actions to craft himself as one of the last true conservative leaders in America -- to become the party's favored standard-bearer for 2020.

The Republican Party didn't appreciate him this time, but after a whooping in the polls this November with Trump, they may well come around to Cruz's vision and gifts.

"A lot of folks in Washington are eager to write the epitaph for the conservative movement," Cruz said Tuesday in his public comments.

That vindication alone may be enough for Ted Cruz to stay Ted Cruz, the guy Washington loves to hate.