As an appetiser before helping to send the US government into famine mode, Ted Cruz railed against Obamacare on the Senate floor last month in a publicity-seeking speech that lasted more than 21 hours and included a Darth Vader impression and reading Dr Seuss's Green Eggs and Ham as a bedtime story for his daughters, who watched on TV.

While the grandstanding was largely symbolic, Cruz has been more than just a figurehead for the Republican showdown over Obamacare that has prompted a government shutdown. The first-term senator from Texas has emerged as an unofficial envoy between conservatives in the House of Representatives and Senate, spending hours with Tea Party supporters such as congressman Justin Amash to plot what, with hindsight, has been a highly orchestrated plan of attack.

It began over the summer with television ads reminding grassroots conservatives that it was not too late to block Obama's four-year-old Affordable Care Act by cutting off its funding. With expectations raised, Cruz ruffled feathers among mainstream Republicans by helping to bounce House speaker John Boehner into a confrontational stand-off over the normally routine continuing budget resolution.

Cruz is used to mainstream Republican opprobrium – John McCain famously described him and fellow conservative Rand Paul as "wacko birds" – but he briefly became the most hated figure in Congress when he then failed to follow through on his strategy by winning enough support in the Senate, leaving Boehner blamed for shutting down the government.

"[Cruz] pushed House Republicans into traffic and wandered away," sniped tax campaigner Grover Norquist in an interview last week.

Since then, however, "Cruz control" has begun to look more sure-footed again. His strategy of blaming Obama for the shutdown by refusing to negotiate is unlikely to succeed in persuading anyone who has been following proceedings closely, but may confuse ordinary voters enough to blame both sides equally. Republicans have also boxed the White House into a corner by selectively offering to fund ideologically favoured bits of the government such as the military and national monuments. Angrily dismissed as a gimmick by the administration which blocked most of these piecemeal measures but was forced to accept others, this tactic has succeeded in making it look as if Obama wanted to keep as many hostages in the room as possible.

Eventually, Boehner may have to cut a deal with moderate Republicans and Democrats that would end the standoff without scrapping Obamacare, but for now the conservative grassroots could not be happier.

Battling the federal government on almost any issue is a crowd-pleasing tactic in Texas, the most stubborn and independent-minded state in the union. "I think he's doing great," said Beth Cubriel, executive director at the Republican party of Texas. "He's a voice for people who are so frustrated that as long as the president has been in power the conservative view has not been covered."

Cruz won an underdog victory in the Texas Republican primary last year, preaching a fiery rightwing gospel that made his establishment-backed opponent, David Dewhurst, seem moderate and mainstream. As a Latino, Cruz helps Texas Republicans to woo an increasingly important and left-leaning demographic while retaining traditional conservative values – even though he comes across as an upstart outsider.

"He ran very effectively as an anti-establishment candidate, however counter-intuitive that seems for a Harvard-educated lawyer," said Jim Henson, director of the Austin-based Texas Politics Project at the University of Texas.

"We couldn't be prouder of Ted Cruz," said Julie Turner, president of the Texas Patriots PAC, a Tea Party group. "Ted Cruz is the tuning fork for the conservative movement." Turner fondly recalled an impromptu pre-election rally near Houston with Cruz and his wife giving speeches from the back of a pick-up truck: "They spoke our values then he went to Washington and followed them."

While Cruz's rise to fame was sudden, Felicia Cravens of the Houston Tea Party Society said that it was carefully planned: "He's been making the circuit of Tea Party events since 2009. He'd go to meetings of any size, speak to as few as 10 people. He put in the shoe leather early on to make contact with people who could be influence-makers."

The 42-year-old was born in Canada, the son of a Cuban father and American mother. He grew up in Houston and went to Princeton and Harvard Law School, where he was seen as brilliant but arrogant.

Then he worked on George W Bush's 2000 presidential campaign. After a period in Washington, Cruz returned to Texas to become solicitor general, overseeing appeal cases and taking on high-profile supreme court battles on topics such as gun rights, abortion and religious symbols. In one of his proudest moments, he helped to persuade the supreme court that Texas had the right to execute a Mexican national convicted of murder, despite opposition from President Bush and the International Court of Justice, which ruled the case should be reopened.

Polls this year suggest that a quarter of Texans adore him and a similar amount loathe him. On Thursday, several dozen department of defence workers protested outside Cruz's San Antonio office, wielding placards with slogans such as "Ted – go furlough yourself".

Bob Comeaux, a Democratic activist, joined them. "I think he is a very fine advocate for the seven or eight per cent of crazy people in the state of Texas," he said. "I have a niece who's a firefighter who's required to go to work for no pay. What kind of a country is that requires people to work for no pay? In Texas it used to be we'd elect politicians to get something done. Now there's a mentality to send people up there [to DC] to make sure nothing gets done."

A meeting of Senate Republicans on Wednesday turned into an anti-Cruz "lynch mob", according to the New York Times. Alienating colleagues is hardly a recipe for longevity in the Senate, especially if Texans conclude Cruz is more interested in his own future than theirs.

"The shelf-life of a very conservative member of the Senate is short," said Brandon Rottinghaus, associate politics professor at the University of Houston. "It's hard to govern if you're outside the boundaries of your party and your tactics are explosive."

But by the time his Senate seat is up for grabs again in 2018, Cruz presumably hopes his cowboy-booted feet will be on the desk of the Oval Office, a maverick intellectual improbably carried to ultimate power by those who love to hate big government. It would be quite a story to tell.