UPDATE: Sen. Ted Cruz and a band of conservative Republicans finished speaking on the U.S. Senate floor after talking through the night for about 21 hours and 19 minutes.

It can't be called a filibuster in the technical sense, but Republican Sen. Ted Cruz and a band of conservative Republicans have been talking on the floor of the U.S. Senate since Tuesday afternoon, continuing through the night and into Wednesday morning, urging fellow lawmakers to defund the health care reform law in the fiscal 2014 spending resolution.

They did not like Obamacare, either. They did not like it in a box with a fox, in a house or with a mouse.

Cruz, a freshman from Texas, began speaking at 2:41 p.m., pledging to keep going until he is "no longer able to stand."

More than 16 hours later, Cruz was still going, with the help of Sen. Marco Rubio, R-Fla.

"We are not fighting here against the president, we are fighting for people," Rubio said, explaining the effort to protest the health care law.

Cruz and company cannot continue indefinitely. Senate rules dictate that a test vote will be called after noon Wednesday that will determine whether to proceed to the resolution. Cruz will have to yield the floor at that time.

He wasn't alone on the floor overnight. Sen. Mike Lee, R-Utah, frequently jumped in to ask questions and contribute to the debate.

"I'm a little tired," Cruz said. "Sen. Lee is a little bit tired."

Cruz wants Republicans to vote against ending debate on a House-passed resolution that will fund the government into the new fiscal year because Democratic Majority Leader Harry Reid, of Nevada, plans to strip out language that would have defunded the health care law.

"Voting to cut off debate is voting to allow the majority leader to gut the bill," Cruz said, referring to Reid's intent to remove the defunding language with an amendment.

Cruz filled hours on the Senate floor, making the case against implementing the health care law, citing negative effects it is having on the economy and job creation as well as the cost and quality of health care.

Cruz aides created a hashtag on Twitter #MakeDClisten, based on the theme of his lengthy talk, and the term was trending at or near the top of the social media site throughout the evening. Cruz read dozens of Twitter messages on the Senate floor from people who oppose the health care law and want Congress to block it.

One GOP Senate aide called Cruz's lengthy floor debate a "huge victory" that will have an impact on the vote.

"No whip count yet but we're feeling good," the aide said.

While the health care law is universally unpopular among Republicans, only a handful of Senate GOP lawmakers plan to side with Cruz in his efforts to block the government funding bill.

Many Republicans fear the party will be blamed for a government shutdown if no resolution is passed by Monday, when the fiscal 2013 budget runs out.

Minority Leader Mitch McConnell of Kentucky and Minority Whip John Cornyn of Texas are among top Republicans who announced they won't block the overall bill. Both men are up for reelection next year.

Cruz noted "there are divisions in the Republican conference" on the issue.

"Let me suggest to my Republican friends [that] we should worry a lot less about blame and politics and just worry about fixing this for the American people," Cruz argued.

He said the chamber should have been full of lawmakers helping him make the case, but instead it was mostly empty.

Around 8 p.m., Cruz read the Dr. Seuss book "Green Eggs and Ham," drawing a comparison to the protagonist's dislike of the green food to the public's opposition to the health care law.

"They did not like Obamacare, either," Cruz said. "They did not like it in a box with a fox, in a house or with a mouse."

About a half-dozen Republicans who back the Cruz strategy joined him on the floor to help him fill the time, including Sen. Rand Paul, R-Ky., Marco Rubio, R-Fla., Jeff Sessions, R-Ala., James Inhofe, R-Okla., and Mike Enzi, R-Wyoming.

Paul conducted a nearly 13-hour filibuster earlier this year, delaying the confirmation vote of CIA Director John Brennan until the White House clarified the government's policy on drone strikes.

Sen. Mike Lee, R-Utah, was a frequent participant in Cruz's overnight talk. Lee authored the pledge to vote against any government funding bill that funds Obamacare, which was signed by 14 GOP senators.

Senate Majority Whip Richard Durbin, D-Ill. and Sen. Tim Kaine, D-Va., separately debated Cruz about the merits of the health care law. Durbin asked Cruz to respond to an unemployed Illinois constituent named Judy who, thanks to the health care law, will be able to enroll in a health care insurance program for the first time.

Cruz said it would be better to create an economy where more people can find work.

"I think your answer to Judy is she needs a better job," Durbin said.