Republican lawmakers are continuing their post-shutdown offensive on Obamacare’s early dysfunction, demanding to know not just how the administration launched an untested website but how much taxpayers are being charged for fixing the flubs.

“The rollout of the Obamacare website was exactly what its supporters predicted – a train wreck. To try and clean up the mess, President Obama is calling up a tech surge to overhaul the website, and sending the bill to the taxpayers,” said Sen. John Cornyn (R-Texas).

“The taxpayers have already shelled out hundreds of millions of dollars to build the original website. How much more money is President Obama going to demand?” Cornyn asked. “Instead of continuing to pour money into this broken law, it’s time to issue a permanent delay and work on solutions that provide real health care reform, rather than broken promises and error messages.”

Sen. Marco Rubio (R-Fla.) warned his constituents to use caution with the Obamacare healthcare exchange site.

“It is clear the Obamacare rollout has been a disaster that has further eroded the American people’s confidence in the federal government’s ability to keep basic promises,” Rubio said. “With all the problems and errors with the ObamaCare website, people should collect as much evidence as they can from their experiences in order to protect themselves from potential fraud, double billing, and penalties once the mandate is enforced.”

“While the errors with the website have been well documented in the media, it’s important that every consumer who is unable to register keep a record of the specific errors they encounter on the website because of the threat of potential government fines for failing to enroll in the future,” Rubio added. “Make no mistake: The IRS will go after anyone who fails to meet the Obamacare requirements, so it’s important that consumers document the online problems.”

The House Energy and Commerce Committee is holding a hearing Thursday on the Obamacare failures. Health and Human Services Secretary Kathleen Sebelius was invited to testify but declined, citing a conflict with her schedule.

“Secretary Sebelius had time for Jon Stewart, and we expect her to have time for Congress,” Chairman Fred Upton (R-Mich.) said in a statement.

Obama said at a healthcare event today that “nobody is madder than me about the fact that the website isn’t working as well as it should, which means it’s going to get fixed.”

“Even with all the problems at, the website is still working for a lot of people — just not as quick or efficient or consistent as we want. And although many of these folks have found that they had to wait longer than they wanted, once they complete the process they’re very happy with the deal that’s available to them,” he said, stressing that people can sign up by phone or in person and bypass the website.

“And, by the way, there are a lot of people who want to take advantage of this who are more comfortable working on the phone anyway or in person,” the president added.

Sen. Lamar Alexander (R-Tenn.), who last week launched an investigation into the testing of the Obamacare site as well as security risks, said “somebody must be accountable for this mess, and if the president isn’t going to resign, it’s up to him to figure out who should.”

“The president is right—this law is more than a website that won’t work—it’s a Washington mandate that many Americans are finding impossible, and it’s an historic mistake that is raising premiums, forcing employees off insurance plans, increasing out-of-pocket costs, and pushing employers to cut jobs and hours,” Alexander said. “His speeches worked during the campaign, but today Americans are still no closer to understanding what has gone wrong with this website, or how it will be fixed, or whether it will be fixed in time for them to comply with the mandate.”

Rubio said he’ll file legislation delaying the individual mandate under Obamacare until six months after the Government Accountability Office (GAO) certifies that the exchange website is fully functional.

“I believe this entire law should, and will, eventually be repealed and replaced. But until that happens, I will continue looking for ways to protect Americans from the disaster that is Obamacare,” Rubio said.

“The legislation, which will be introduced when the U.S. Senate reconvenes next week, would delay the individual mandate until six months after the GAO certifies the websites and all other sign-up options (phone, mail, fax) are fully functional. Thereafter, it exempts people from paying the mandate fines if they can prove that they tried to sign up but could not because of technical or customer service issues.”