The questions about Ted Cruz in the Senate no longer start with whether he’s got even a couple of friends left among fellow Republicans. The answer, after a public shaming on the floor last week, sure looks like a “no.”  

As to whether he’s bothered by his deepening isolation in the Capitol, that’s just as easily answered in the negative. To the contrary, he’s acting as though it’s one of the best things going for him in his presidential campaign. And if the Texan doesn’t end up in the White House, would he have a chance to rehabilitate his standing as a senator? On that, there’s a growing divide of opinion.  

But would he want to? That will remain a mystery at least for the next few months, and maybe for longer than a year.  

Much of the congressional curiosity about Cruz has to do with his unique positioning on the American political org chart. No lawmaker in modern times has worked as transparently to win promotion to the presidency by biting the political hands that have fed him and burning down the place where he works .  

No one in recent memory has made so strong a negative first impression in the Senate and then expanded it so dramatically among colleagues in both parties. And none of the three other Republican senators running nationwide in 2016 faces the prospect, if things don’t work out, of being called to run again back home just two years later.  

Marco Rubio is giving up his Florida seat, Rand Paul is now bidding simultaneously for president and for re-election in Kentucky and Lindsey Graham’s third term in South Carolina lasts until 2020. But Cruz is up in 2018.  

Talking last week with almost a dozen other GOP senators and players in Texas Republican politics turned up nothing about the party’s establishment wing plotting already to topple Cruz in a primary. But there was plenty of worry he would be vulnerable to defeat by a Democrat, especially one who excites the state’s growing Hispanic electorate and leverages the incumbent’s polarizing nature into copious amounts of campaign cash.  

Instead, most of these Republicans speculated Cruz is as likely as not to give up on his mutually antagonistic relationship with the Senate after a single term. He would be 48 then, presumably with many opportunities for advancing his tea party agenda in lucrative and telegenic, as well as influential, ways.  

(Departing so soon, and on his own terms, would be huge break with Texas political tradition. The last elected senator from the state who retired after one term was Democrat Horace Chilton, in 1900.)  

“Oh, I’m not really at all sure that’s what he wants,” Phil Gramm, a senator from 1985 through 2002, said when asked if his fellow Texas Republican has a long-term future in the Senate among his career options.  

Gramm said that, in frequent conversations with Cruz, he’s described his own influence increasing after waging his 1996 presidential bid on combative conservative grounds. “Everyone has their own approach, and there’s still time for him to change his,” Gramm said when asked about Cruz’s no-hold-barred style for dealing with other Republicans. “It may well be Ted’s approach won’t be the same as mine.”  

But it’s already too late for Cruz to change his stripes, his presidential rival Paul told Fox News Radio last week.  

“Ted has chosen to make this really personal and call people dishonest in leadership and call them names, which really goes against the decorum and also against the rules of the Senate,” he said. “And as a consequence, he can’t get anything done legislatively. He is pretty much done for and stifled and it’s really because of personal relationships, or lack of personal relationships. And it is a problem.”  

Paul spoke after Cruz endured one of the more dramatic parliamentary putdowns of recent senatorial vintage. Two nights before Congress cleared stopgap spending legislation averting a partial government shutdown, he sought a roll call vote on adding language defunding Planned Parenthood — and fellow Republicans were not willing to provide the necessary seconds for the motion.  

His amendment was then defeated on a voice vote with the vocal backing of only one other GOP senator, Utah’s Mike Lee. And then, adding insult to injury, no other senator in his own party was willing to support Cruz’s effort to keep railing about the situation for longer than his allotted hour.  

“That was very instructive” about Cruz’s standing in the cloakroom, said John McCain, who’s cultivated a reputation as a just-short-of-the-line GOP maverick during 29 years as a senator from Arizona. “I’ve never before seen a senator who couldn’t get even one other person in the Senate to raise his hand to help him get a vote.”  

Asked to choose sides between Cruz and Mitch McConnell, the contest isn’t even close. The Texan’s crusade against the Kentuckian’s tactics, which even included accusing the majority leader of telling “a flat-out lie” this summer, has totally backfired.  

Positioning himself as the leading outsider who’s inside Congress may have ostracized him in the Senate. But it continues to provide him a cult following in the House , where his efforts to steel the spines of the GOP “Hell no” caucus over cheap Tex-Mex at Tortilla Coast on the Hill remain the stuff of legend.  

His orchestrated combativeness, however, has not yielded a breakout moment for his real quest. He now stands sixth in popularity among the presidential candidates, averaging 6 percent in the past half-dozen national polls. That’s up a couple of notches from his low point of 4 percent in July. But two years ago this month, when he was a driving force behind the last government shutdown, he was the presidential preference of 12 percent and No. 3 in the just-forming field.  

(In a further sign the Cruz strategy isn’t working, he’s slipped 5 points behind Donald Trump as the first choice of his home-state Republicans, according to a poll by the Texas Lyceum released last week.)  

In the coming weeks, a requisite debt limit increase and an inevitable breach of the sequester spending caps will afford Cruz at least two more long-shot opportunities for trying to harness congressional dramatics to the cause of his presidential campaign. He’s got little incentive to let those pass him by.

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