Sen. Ted Cruz, (R-Texas), said on the Senate floor Tuesday he would stand against the president's health care law "until I'm no longer able to stand." (The Washington Post)

Continuing his vow to keep speaking against the new federal health-care law "until I am no longer able to stand," Sen. Ted Cruz (R-Tex.) continued with his marathon speech modeled on old-fashioned filibusters Tuesday evening in hopes of slowing debate over a short-term spending measure.

"I rise today in opposition to Obamacare," Cruz announced as he began his remarks Tuesday afternoon, saying he would be speaking on behalf of millions of Texans and Americans opposed to the new health-care law.

"A great many Texans, a great many Americans feel they do not have a voice, and so I hope to play some very small role in providing the voice," he said.

(Watch: Highlights from Cruz's marathon speech (so far) )

Shortly after 8 p.m., Cruz announced he would begin reading "bedtime stories" to his two young daughters, who he said were back home in Texas watching with his wife. Cruz started with the Bible, quoting from "King Solomon's Wise Words" from the Book of Proverbs. Then he read the Dr. Seuss classic, "Green Eggs and Ham," in its entirety, noting that it was one of his favorite children's books.

When he was done reading, Cruz told his daughters: "I love with you all my heart. It's bed time, give mommy a hug and a kiss, brush your teeth, say your prayers and daddy's going to be home soon to read to you in person."

By holding the floor, Cruz and his allies are launching what most Americans know as a traditional filibuster, or the practice of holding the chamber for several hours on end by speaking continuously, an exercise perhaps best epitomized by actor Jimmy Stewart in the movie "Mr. Smith Goes to Washington."

But even if Cruz were physically capable of speaking for more than 24 hours -- the longest filibuster in U.S. history is 24 hours, 18 minutes by the late Sen. Strom Thurmond (S.C.) and other Southern senators opposed to civil rights laws -- there are already parliamentary procedures in place that dictate that Cruz will have to yield the floor by Wednesday afternoon at the latest.

At that point, the Senate is scheduled to hold a key procedural test vote that is near certain to pass with bipartisan support.

Cruz, a freshman senator, was joined in his efforts by several other Republican senators, including Mike Lee (Utah), David Vitter (La.), Rand Paul (Ky.), Pat Roberts (Kan.), Jeff Sessions (Ala.) and Marco Rubio (Fla.). Paul even sent a callout on Twitter asking supporters to send him questions that he said he would ask Cruz later on the Senate floor. Rep. Paul Broun (R-Ga.), who is running for an open U.S. Senate seat next year, also visited the Senate to watch Cruz speak.

Aides to the senators gave no sense of when Cruz and his allies would conclude, but Cruz is likely angling to match the duration of two other recent filibusters. One, led by Paul in March, lasted nearly 13 hours, while a filibuster by Texas Democratic state Sen. Wendy Davis in June lasted just under 11 hours.

After a little more than two hours, Cruz had discussed an unusual mix of subjects, ranging from opposition to the health-care law; the unemployment rate among African American teenagers; how his father, Rafael Cruz, used to make green eggs and ham for breakfast; a recent awards show acceptance speech by actor Ashton Kutcher; and the fast-food restaurants Denny's, Benihana and White Castle.

When he yielded briefly to take questions, the other senators would give extended remarks on their opposition to the health-care law and then ask Cruz questions that set up the Texas senator to continue his remarks. Meanwhile junior Democratic senators, who by tradition are tasked with presiding over the chamber, sat at the front of the room watching the exchange. Sen. Joe Manchin III (D-W. Va.) sat in the chair watching intently, while Sen. Elizabeth Warren (D-Mass.) was seen using an iPad.

Cruz and Lee have vowed to use whatever Senate procedural tactics are available to slow debate on the legislation. Their marathon speech is the culmination of a strategy they began developing in the summer, when Lee started looking for allies in a move to defund the health-care law by using annual spending bills for federal agencies as potential leverage.

Last week, the House passed a spending measure that would continue funding government operations by also defunding Obamacare, thus avoiding a government shutdown. The bill is now in the Senate, where Majority Leader Harry M. Reid (D-Nev.) has vowed to remove language defunding the law before calling a final vote. Cruz and his allies are hoping to stop Reid from doing so.

But Cruz and Lee have clashed with other Senate Republicans, who strongly objected to their plans in the days leading up to the start of the marathon speech. During their weekly luncheon earlier Tuesday, fellow Republicans urged Cruz to stand down and agree to quickly pass the spending measure and send it back to the House for potential amendments, according to two senators in the room.

Cruz refused the request, the senators said, meaning the Senate likely will have to continue debating the measure through the weekend, giving the House  just a few hours to pass a new spending bill by the Oct. 1 deadline or face a government shutdown.

Asked as he left the lunch how long he planned to speak on the Senate floor, Cruz told reporters: "We shall see."

Moments later, Sen. Orrin Hatch (R-Utah) told reporters that he disagreed with Lee's assertions that there is considerable grass-roots support to defund the health-care law.

"There’s a lot of people upset on both sides, and I just don’t believe anybody benefits from shutting the government down, and certainly Republicans don’t. We learned that in 1995," Hatch said, referring to the last time congressional Republicans clashed with a Democratic president over federal spending.

“We’re in the minority, we have to find a way of standing up for our principles without immolating ourselves in front of everybody, in a way when we don’t have the votes to do it," he said.

Minority Leader Mitch McConnell (R-Ky.) said he also agreed with other Republicans that the Senate should move quickly to pass the spending measure and return it to the House.

"My own view is that it would be to the advantage of our colleagues in the House, who are in the majority, to shorten the process, and if the majority leader were to ask us to shorten the process, I would not object," McConnell told reporters.

"If the House doesn't get what we send over there until Monday, they're in a pretty tough spot," McConnell said later. "My own view is the House, having passed a bill that I really like and that I support, I hate to put them in a tough spot."

Rosalind S. Helderman and Lori Montgomery contributed to this report.

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