U.S. Republican Senator Ted Cruz slogged into the second day of his marathon attack on Obamacare from the Senate floor on Wednesday, showing almost no signs of relenting after speaking for more than 17 hours.

Standing in a nearly empty Senate chamber, Cruz made his case to deny funding to implement President Barack Obama's landmark overhaul of the U.S. health care system, calling it the country's "biggest jobs killer."

Most of the Tea Party firebrand's Republican colleagues shunned his diatribe against the health insurance reform law, which is delaying Senate debate on a short-term funding measure needed to avoid a government shutdown in six days.

Elected from Texas last November, Cruz at times strides the U.S. Capitol attired in cowboy boots. But on Wednesday morning, his feet were clad in tennis shoes. In black, they matched his suit.

"Obamacare isn't working," he said in between stories about the struggles of his Cuban immigrant father and reciting Doctor Seuss verse. A professed carnivore, he also used his time to recount the tribulations of Christmas dinner with his future wife's vegetarian family.

Cruz began talking at 2:41 p.m. ET on Tuesday. His performance had the look of a filibuster, where a legislator draws out a speech as long as possible to try to block legislation. Except in this case, it won't.

Under Senate rules, Cruz must yield the floor by noon Wednesday for a procedural vote that will start the Senate toward final passage of the bill to keep government agencies funded through Nov. 15 — including Obamacare money.

Budget Battle Cruz

Senator Ted Cruz, a Texas Republican, is seen on a TV screen in the U.S. Senate press gallery during the tenth hour of his marathon speech on the Senate floor early Wednesday morning. (Evan Vucci/Associated Press)

In the early hours of Wednesday morning, Cruz was joined on the Senate floor only by Republican Senator Mike Lee of Utah, who provided him short breaks from speaking. Lee and Cruz spent the summer whipping up conservative anger against the health care law.

As dawn approached, Senator Marco Rubio of Florida, also a Tea Party conservative, took the lectern, giving Cruz a break, which the Texas lawmaker used to stretch with knee bends on the Senate's floor.

Republicans agree with Cruz's contention that Obamacare is a "disaster," but most of the 46 Senate Republicans are expected to line up instead with their party leaders in support of the emergency spending bill.

Cruz wants to block the funding measure unless it contains no money to implement Obamacare.

The health care law aims to provide health coverage to millions of uninsured people, but it has met fierce opposition from American right-wingers.

The Republican-controlled House of Representatives last week passed a version of the spending measure that denied funds to Obamacare. That will be stripped from the Senate version, which also will be shorter.

The House will have to decide whether to pass the revised bill or find a compromise with the Senate. Unless new funding is quickly approved, a government shutdown would begin on Tuesday.

Republicans uniformly want to repeal Obamacare. But many see that as a political impossibility as long as Democrats control the Senate and hold the presidency.