Political fallout is spreading ahead of an oil slick that weather forecasters warn might reach Gulf Coast beaches by this weekend.

Offshore, cleanup workers struggled to contain an oily sheen spreading from a well ruptured by the explosion and sinking of the Deepwater Horizon exploration platform. Coast Guard officials estimate that some 42,000 gallons of crude continue to leak into the Gulf of Mexico each day. Remote submersibles have so far failed in an effort to close the shattered well's blowout valve, which should have shut off automatically. Boom crews plan to begin burning collected oil on the Gulf's surface as early as Wednesday.

In Port Fourchon in Louisiana, contractors for BP are fabricating a second line of defense: an undersea containment chamber designed to shroud the leaking pipe. Oil could then be pumped to the surface for recovery. The collection technique has never been attempted at such depth, but officials say it's the best hope for a quick fix. The alternative — relief wells drilled by a platform floated into place Tuesday — could take up to three months.

The irregular shape of the growing oil slick makes it difficult to estimate the pollution's total area. The Coast Guard says oil is now within 20 miles of the sensitive Delta National Wildlife Refuge. Weather forecasters are keeping an eye on an approaching storm system powerful enough to bring the slick to the northern Gulf Coast by this weekend.

The investigations begin

With the prospect of oil reaching the coast's pristine white beaches and prime marine breeding grounds, politicians have begun to call for a review of oil industry safety claims. The timing couldn't be worse for the Obama administration, which just last month reversed decades-old policies and threw open large sections of the Atlantic, Gulf and Alaskan coasts to new drilling and exploration.

The first volley in what is likely to become a round of Congressional hearings was sounded by U.S. House Energy and Commerce Committee Chairman Henry A. Waxman (D-Calif.) and Oversight and Investigations Subcommittee Chairman Bart Stupak (D-Mich.). Both sent letters Tuesday to Transocean LTD, owners of the stricken Gulf rig, inquiring about the company's response plans in the event of accidental oil or natural gas release. On the Senate side, longtime drilling opponents Bill Nelson (D-Fla.), Frank Lautenberg (D-N.J.), and Robert Menendez (D-N.J.) called upon heads of the powerful Senate Energy and Commerce committees to re-examine oil industry safety claims.

Two Cabinet-level officials also announced the launch of joint investigations. Department of the Interior Secretary Ken Salazar and Department of Homeland Security Secretary Janet Napolitano said Tuesday that they have begun formal investigations into the cause of the Deepwater Horizon explosions, and what methods may exist to prevent similar occurrences in the future.

Wither Charlie Crist?

But the big driver of Gulf drilling policy has always been Florida, with its strong political clout and long, heavily populated coastline. There's no more central figure on the issue than Republican Gov. Charlie Crist, who spent most of his career in lockstep with the state's Congressional delegation against the expansion of offshore oil development.

Florida Governor Charlie CristCrist stung his environmental allies in 2008 when he began to soften his stance on drilling. He embraced then-presidential candidate John McCain's call for exploratory drilling off the Florida coast, citing high gasoline prices and the "suffering" of Florida residents. The flip-flop was immediately condemned by Barack Obama, who campaigned on the proposition that renewed oil and gas exploration would have little effect on consumer prices.

Now Crist and Obama may again be exchanging positions. The president so far remains committed to his new pro-drilling policies. Crist, on the other hand, appeared to be rethinking his support after taking an aerial survey of the spill with state Environmental Secretary Michael Sole Tuesday afternoon. According to the Pensacola News Journal, Crist called the spill "absolutely unbelievable in its magnitude" and said that operations like Deepwater Horizon rig were "not far enough ... not safe enough, and obviously not clean enough."

There are also high-stake state politics in play. Crist is in a losing battle for the GOP Senate nomination with Marco Rubio. He's under wilting pressure from national Republicans to step aside in favor of the surging Miami lawyer, and Crist is now openly entertaining the idea of an independent Senate candidacy. With Rubio firmly in the pro-drilling camp, the specter of crude oil washing up on Florida's white sand beaches at the height of tourist season may give Crist an emotionally charged wedge issue — should he choose to bolt the GOP. An announcement is expected on Thursday.

Heavy weather

Meanwhile, the slick continues to spread across Gulf waters. Forecasters at AccuWeather warn that a strong system moving through the nation's midsection and expected to arrive in the spill area by Friday could push oil ashore this weekend. A similar front disrupted cleanup operations late last week.

The gathering spring storm seems an appropriate idiom for political forces aligning to contest the petroleum industry's reputation of technical safety. If the spill continues to gush for weeks or months, it could be a long, sticky summer for the Obama administration and its oil company allies.

Chris Baskind is an environmental writer living in Pensacola, Fla., within view of the threatened beaches. He's blogging about the spill on his personal site, and can be followed on Twitter and Facebook.

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No new drilling until answers on accident