A lobbying firm with ties to Washington state's congressional delegation worked on a controversial federal loan guarantee for Solyndra, the bankrupt California solar company at the center of a growing political scandal.

Solyndra, once touted as a stimulus success story by the Obama administration, shut down Aug. 31, despite having received a $535 million loan guarantee in 2009. The FBI raided the company's headquarters last week and Congressional Republicans have launched an investigation, citing emails they say show the administration ignored warnings to speedily approve the federal loan.

McBee Strategic Consulting, a lobbying firm founded by Steve McBee, a former aide to Rep. Norm Dicks (D-Bremerton), was hired by Solyndra in 2009 to work on the Department of Energy loan guarantees, according to lobbying disclosures filed with the U.S. Senate.

McBee did not return a phone call Thursday seeking comment on the company's work for Solyndra. There has been no indication the lobbying firm did anything illegal.

Several McBee lobbyists worked on the solar company's behalf, including McBee himself, as well as Angela Becker-Dippmann, a former aide to Sen. Maria Cantwell (D-Wash), and Jeff Markey, a former aide to Rep. Doc Hastings (R-Pasco), the lobbying disclosures show.

In all, the firm was paid $380,000 by Solyndra between 2009 and this year to work on the loan guarantees as well as federal legislation to benefit the solar-power industry, according to data maintained by OpenSecrets.org.

McBee, whose firm has offices in Seattle, Washington D.C. and Palo Alto, Calif., has repeatedly been hailed as one of the top lobbyists in D.C. in recent years, in part due to his firm's ties with Northwest lawmakers like Dicks and U.S. Sen. Patty Murray. (Murray's former chief of staff, Rick Desimone, also works for the firm.)

For McBee, lobbying for green power clients like Solyndra has proved lucrative, making up for the slowdown of federal earmarks. In a 2009 interview with Roll Call, McBee attributed his firm's soaring revenues, in part, to "the bets we've made on clean energy."

Solyndra's hiring of McBee coincided with a push to get the federal loan implemented as part of the 2009 stimulus package, according to multiple media accounts and documents released by a U.S. House committee investigating the loan.

While Democrats have pointed out the government began moving toward approving the loan during the Bush administration, Solyndra is rapidly becoming an embarrassment for the Obama White House.

Administration officials repeatedly praised the solar company as a symbol of how the stimulus could get people back to work while investing in a clean-energy future for America. Vice President Joseph Biden and Energy Secretary Steven Chu attended the groundbreaking for the company's Fremont, Calif. plant in Sept. 2009, and Obama personally toured the company last May.

In August, Solyndra filed for bankruptcy, shutting down its plant and laying off 1,100 employees. On Sept. 8, the FBI raided the company's headquarters as part of an apparent investigation.

Republicans have accused the Obama administration of rushing through the Solyndra loan, despite some questions about the company's stability. House Republicans have launched an investigation, and grilled administration officials at a hearing on Wednesday.

The Washington Post reported this week on emails which the paper said showed White House officials pressured loan reviewers to speed up approval of the Solyndra loan, an allegation the White House has denied.