Politics may be stressful, but that doesn’t mean anyone in politics loses weight accidentally. When they begin looking trim in better-cut suits, then you know something’s afoot.

Ted Cruz is looking trim these days.

And while he has kept a relatively low profile during this year’s elections, his new look, along with his numerous trips to early-voting states like Iowa and South Carolina, means it’s safe to conclude that he’s seriously considering a run for the Republican presidential nomination in 2016. If so, he’ll have a long road ahead to build the type of national organization and national stature necessary for a presidential run. But he’ll be in a better position to do so than his critics might think. His insurrectionist ethos in the Senate, especially during his 2013 campaign to defund the Affordable Care Act, made a lasting impression on primary voters around the country; in September, he won the straw poll at the Values Voters Summit, for the second year in a row. Cruz’s support among the base should be enough to give him a hearing in a crowded primary field. 

As his team begins to consider the road ahead and other contenders size up what he would be like on the campaign trail, it’s clear that he has serious weaknesses—but his greatest weakness is not his most obvious one.

The most obvious one is that he’s unpopular and divisive. Polls show him as one of the least well-liked prospects in the Republican field, and he trails Hillary Clinton in hypothetical matchups. It’s far too early for the polls to have predictive value, but they do point to the fact that there’s nothing about Cruz that overtly says “big tent” or “broad coalition,” two hallmarks of most successful bids to win more than 270 electoral votes in a nation of 330 million people. Even before he was elected to the Senate in 2012, he had been typed as a Tea Party firebrand, having won the Republican nomination after a ferociously contested primary runoff against Texas’s incumbent lieutenant governor, David Dewhurst. During his first months in the Senate, he did nothing to dispel that impression. And by the end of 2013, his campaign to defund the Affordable Care Act seemingly triggered a government shutdown and nearly led the country to default on its debt. Plenty of people, on both sides, saw him as reckless, a demagogue and a bully, and his favorability ratings reflect that.

As obvious as this problem is, Cruz will probably be able to overcome it. As the hubbub over the shutdown has subsided, so too has the rhetoric over its ringleaders. The record will show that the formal cause of the shutdown was the House, and Cruz, as a senator, has an alibi for that. Meanwhile, having led the defunding campaign, he can reasonably argue that he led the Republican opposition to stop Obamacare. That’s impressive, considering that he wasn’t even in public office when the law was passed, and it’s not a bad campaign credential; if you’re going to demagogue, you might as well demagogue on the only issue that unites and animates the entire Republican coalition, an issue that remains, as the vice-president once put it, “a big f-ing deal.” As for the idea that Cruz is a bully—well, let’s get the guy on a stage with Chris Christie and see which one flips out first.

Cruz’s greater liability—and the one that might be hardest to overcome on the trail—is his inexperience. This is his greatest liability, in fact, because it’s real. He’s about to turn 44, meaning that he’d be one of the youngest presidents ever elected if he won in 2016, and nearly an entire generation younger than, say, a Hillary Clinton or most of the other likely Democratic candidates. He was only elected to the Senate in 2012; he never even ran for office before that, though he served as Texas’s solicitor general under attorney general Greg Abbott. Since arriving in Washington, he has made an outsized impression in his role as a low-ranking member of the Senate’s Republican minority, but his ability to wield power, rather than simply making trouble for those who do, is as yet untested. He has never weathered the unforgiving spotlight of a national campaign, never even really faced the barrage of opposition researchers, negative ads and whisper campaigns that would inevitably come with a presidential bid.

He faces a long, uphill battle to be president, especially because of where he sits today. Widespread frustration with Washington bodes well for Republican governors who might be eyeing the nomination—including, perhaps, Cruz's own governor, Rick Perry. Setting that aside, there’s not much history of U.S. Senators rising directly to the presidency. While 16 senators have eventually become president, only three have moved directly from the Senate to the White House. The good news for Cruz is that all three did it in their first term as senator, including Warren Harding in 1920 and John F. Kennedy in 1960.

It’s the third senator-turned-president who represents perhaps the clearest precedent for Cruz, but it’s not exactly an example that Cruz can point to easily on the campaign trail—or even whisper to potential donors behind closed doors.

In fact, the best analogue for the race Cruz may hope to run is another young senator with little managerial experience who had never faced a negative campaign before running for president.

Back when he was the junior senator from Illinois, Barack Obama sometimes invoked Martin Luther King Jr.’s comments about “the fierce urgency of now” to explain why he was running for president. “I believe that there's such a thing as being too late,” Obama added on one such occasion, “And that hour is almost upon us.” That was at the Democratic National Committee’s fall meeting in Washington, in November 2007. His point was that the country couldn’t afford four more years under a Republican president. But the Iowa caucus was as yet six weeks away, and that being the case, the comment carried an additional implication. A number of Democrats, not only his rivals, had questioned whether Obama had the experience to serve as president. He had only been elected to the U.S. Senate in 2004, and his public profile far exceeded his legislative record. The candidate himself, it seemed, had anticipated this line of criticism and decided to dismiss it. After all, there was a lot at stake, perhaps even the survival of the republic.