The Obama administration restructured a half-billion dollar federal loan to a troubled solar energy company in such a way that private investors — including a fundraiser for President Barack Obama — moved ahead of taxpayers for repayment in case of a default, government records show.

Administration officials defended the loan restructuring, saying that without an infusion of cash earlier this year, solar panel maker Solyndra Inc. would likely have faced immediate bankruptcy, putting more than 1,000 people out of work.

Even with the federal help, Solyndra filed for Chapter 11 bankruptcy protection earlier this month and laid off its 1,100 employees.

The Fremont, Calif.-based company was the first renewable-energy company to receive a loan guarantee under a stimulus-law program to encourage green energy and was frequently touted by the Obama administration as a model.

Obama visited the company’s Silicon Valley headquarters last year, and Vice President Joe Biden spoke by satellite at its groundbreaking.

Since then, the implosion of the company and revelations that the administration hurried Office of Management and Budget officials to finish their review of the loan in time for the September 2009 groundbreaking has become an embarrassment for Obama as he sells his new job-creation program around the country.

An Associated Press review of regulatory filings shows that Solyndra was hemorrhaging hundreds of millions of dollars for years before the Obama administration signed off on the original $535 million loan guarantee in September 2009. The company eventually got $528 million.

Given the company’s shaky financial condition, Republican lawmakers say the decision to restructure the loan raises questions about whether the administration protected political supporters at taxpayers’ expense.

“You should have protected the taxpayers and made some forceful actions here after this analysis,” Rep. Cliff Stearns, R-Fla., told a top Energy Department official this week. “Because you should have seen the problems. And you should have said, ‘Taxpayers need to be protected and this has got to stop.’ “

The loan restructuring is one element congressional investigators are focusing on as they look into the federal loan guarantee Solyndra received under the economic stimulus law.

Under terms of the February loan restructuring, two private investors — Argonaut Ventures I LLC and Madrone Partners LP — stand to be repaid before the U.S. government if the solar company is liquidated.

The two firms gave the company a total of $69 million in emergency loans. The loans are the only portion of their investments that have repayment priority above the U.S. government.