Texas senator jumps from children's books to the civil war in bid to block parts of bill that would extend health insurance in the US

Texan Republican Ted Cruz talked through the night in a marathon speech against Obamacare, in a show of congressional theatrics devoid anything other than symbolic consequence.

Reading from children's books to keep going, a tired-looking Cruz was joined in shifts by fellow conservatives Marco Rubio, Rand Paul and Pat Roberts in a stand against Barack Obama's plan to extend health insurance in the US.

Cruz's speech was not technically a filibuster, as it he was merely speaking during a permitted time slot. Nevertheless he gave one of the longest Senate performances ever, stopping after 21 hours 19 minutes, with occasional remarks by other conservative senators.

The speech was ostensibly intended to hold up the passage of what is known as a continuing resolution: a motion to maintain funding for the federal government. The resolution passed the House of Representatives on Friday, but is the subject of controversy because Republicans tacked on a provision that would defund the non-mandatory elements of the Affordable Care Act.

But there was never a chance that the resolution would be delayed: Cruz always knew that he would have to give way to a procedural vote. Indeed, after sitting down, he joined every other senator in allowing debate on the resolution to continue.

Some Republicans have disavowed Cruz's tactics. A number are fearful that they will be blamed for the consequences of a government shutdown and, others complain of the difficulty of explaining Cruz's position: attempting to block a measure that he supports.

But Cruz's tactics did at least ensure proceedings went at the slowest possible pace.

If his pseudo-filibuster had lasted until 3pm Wednesday, Cruz would have broken the record for the longest-ever Senate speech set by Strom Thurmond in 1957 in an attempt to prevent passage of the Civil Rights Act.

Cruz began speaking out against Obamacare at 2.40pm on Tuesday and vowed to keep going until he was "no longer able to stand".

Republican leaders, who have disavowed Cruz and his fellow hardliners, had hoped that they might be able to ensure a swift Senate vote so that they had time to avoid a government shutdown when the legislation is passed back to the House of Representatives for a final showdown before Monday night's deadline.

But Cruz has dismissed this as defeatism and is calling for Senate Republicans to block passage of the whole budget bill when they vote on Friday or Saturday so as to stop Democrats from stripping out language that would defund Obamacare.

Comparing the Senate procedures to a "rigged wrestling contest", he declared: "Most Americans could not give a flying flip about a bunch of politicians in Washington. Who cares? Almost all of us are in cheap suits with bad haircuts! Who cares?"

Cruz's own suit remained unruffled throughout, although at one stage Kansas senator Pat Roberts appeared with his tie hanging at half mast. The Texan first-term senator also revealed that he had swapped his usual ostrich-skin "argument boots" for a pair of black tennis shoes after taking advice from Rand Paul, who staged a shorter filibuster last year against US drone strikes.

Invoking the second world war, civil war, war of independence and space race in his favour, Cruz rarely skipped a beat as the night wore on, but his eyelids were visibly drooping by dawn.

At an early stage, he read the Dr Seuss children's classic Green Eggs and Ham, which he billed as a bedtime story to his daughters. While the tactic had charm, some commentators pointed out that the book may not have been the best choice: "The narrator keeps insisting that he hates green eggs and ham, but he's never had green eggs and ham," wrote Matt Iglesias at Slate. "When he finally tries them – he likes them! The Democrats' bet on the Affordable Care Act is that it's like green eggs and ham – they're convinced the public will like it when they try it.

Nevertheless, Cruz ploughed on. Citing sources as varied as actor Ashton Kutcher and the Denny's restaurant chain, he also deployed the fiery rhetoric that has made him a 2016 presidential favourite among Tea Party conservatives.

"We need to make DC listen," he said. "Make them listen to the single mom working in the diner, struggling to feed her kids who has just been told she has to take a cut in hours due to Obamacare."

Cruz took breaks of up to an hour while yielding to questions from supportive Republicans but was also challenged by Democrat Tim Kaine who defended Obama's plan to extend health insurance to low-wage Americans. At one stage, senator Marco Rubio recited a story about Venezuelan toilet paper factories.

Hours before the speech started, Republican Senate leaders Mitch McConnell and John Cornyn refused to back a Cruz plan to block the resolution, opening the way for Democrat majority leader Harry Reid to schedule the first in a series of procedural votes starting on Wednesday afternoon.

"Senator McConnell supports the House Republicans' bill and will not vote to block it, since it defunds Obamacare and funds the government without increasing spending by a penny," a spokesman for McConnell said in a statement.

Senate majority leader Reid was also adamant that Cruz would not be allowed to frustrate passage of the bill any further. "I want to make sure everyone understands: There is no filibuster today," declared Reid at the outset of Tuesday's session.

Cruz also appeared to acknowledge that he had lost Republican support in the Senate, complaining that lawmakers on both sides were preparing to give away their filibuster rights by allowing Democrats to hold a simple majority vote on future amendments. "Our leaders, in both parties, are asking us to vote on a bill without knowing what is in it," he said.

Reid will bring a so-called motion to proceed vote on Wednesday followed by a cloture vote to end debate on Friday or Saturday. This requires 60 votes to pass, but without the support of Republican leaders, Cruz and Lee are unlikely to stop it going through.

After that, Reid is free to introduce an amendment on Sunday to the original budget resolution which strips out the threat to defund Obamacare and only requires 51 votes to pass.

This would mean a so-called "clean" budget resolution will be sent back to the House on Monday with only hours to go until the government funding authorisation expires.

Republicans may still choose to force a government shut down at this point, but speaker John Boehner is increasingly expected to allow a vote that would pass the budget resolution with help from Democrats and a minority of House Republicans.