WASHINGTON—The political fallout of the Gulf of Mexico oil spill could affect the Capitol Hill agendas of the risk management and property/casualty insurance industries this summer and beyond, Washington observers say.

The oil spill and its aftermath are among environmental issues likely to play out on the Hill this summer.

And even though the House has approved the most far-reaching financial services regulatory reform bill in decades, the Senate must follow suit after its current recess, and passage is by no means assured. If the bill wins Senate approval and is signed into law by President Obama, regulations implementing the measure must be worked out. That process could take years.

Other issues, including subjecting certain reinsurance transactions to new taxes, also are likely to get an airing on the Hill this summer. All of this is a prelude to November's midterm congressional elections, where the question is not whether Republicans will pick up seats but rather how many they will gain.

Right now, environmental and natural catastrophe-related legislation appears likely to be an area of major activity.

Ben McKay, senior vp of the Property Casualty Insurers Assn. of America's Washington office, said three natural catastrophe measures could get an airing. One would reform the National Flood Insurance Program, a second would require the NFIP to offer windstorm coverage and the third would have the federal government backstop state catastrophe insurance programs.

Mr. McKay noted that if predictions of an unusually active hurricane season pan out, an “active legislative season” could result.

He said the industry is tracking bills related to the Gulf oil spill caused by the April destruction of the Deepwater Horizon oil platform, operated by BP P.L.C. The question is how spill-related bills will affect insurance, he said.

Frank Nutter, president of the Washington-based Reinsurance Assn. of America, said he has been meeting with congressional staffs “to make certain that they don't do anything to impair insurance contracts through the use of any retroactive change in the Oil Pollution Act.” He said OPA's $75 million liability cap is “highly likely” to increase.

Mr. Nutter said the RAA has advised congressional staffers not to assume that there would be capacity in the energy insurance market to cover a greatly increased cap. He noted that the Insurance Information Institute has estimated that total capacity is not much more than $3 billion, but Congress is considering a $10 billion cap.

The oil spill issue will continue to dominate discussion; and if congressional moves do not directly affect insurance, they could raise questions of litigation, said Leigh Ann Pusey, president and CEO of the American Insurance Assn. in Washington. “There will be no letting this crisis go to waste by folks who want to revisit old issues” such as Superfund liability, she said. The Obama administration wants to reinstate Superfund taxes, which could reopen the Superfund liability debate.

“All hands are out to BP” to try to collect damages resulting from the spill, said Mr. McKay. If BP can't meet its obligations, “people would be looking for another deep pocket.”

“We are certainly concerned about any new revenue raisers as Congress continues to spend and spend,” said Jimi Grande, a senior vp in the Washington office of the National Assn. of Mutual Insurance Cos. Eventually, lawmakers will seek new ways to raise revenue “and the insurance industry is always an attractive target.”

The “most important thing this term remains the financial reform package and related implementation issues,” said the AIA's Ms. Pusey.

“You probably will have 10 times as many pages of regulations as you do of the statute,” which is about 2,000 pages, said Mr. McKay. The question of how to implement the regulations the “right way” is “going to occupy a lot of the industry's time going into the next four or five years,” he said.

For the Risk & Insurance Management Society Inc., the biggest issue is a proposed tax on certain reinsurance transactions, said Scott Clark, RIMS secretary and director-external affairs. Imposing a new tax could restrict capacity, particularly in areas with high-risk coverage needs, said Mr. Clark, who also is risk and benefits officer for Miami-Dade Public Schools in Miami.

More expensive reinsurance would increase premium costs as well, he said.

RIMS also plans to submit a comment letter in support of the federal terrorism insurance backstop program to the Treasury Department, which is seeking comments on the program. The program is slated to expire in 2014.

Terrorism insurance also is of interest to the Council of Insurance Agents & Brokers.

“We're giving a considerable amount of our attention to responding to the Treasury request for information on terrorism coverage,” said Joel Wood, CIAB senior vp. “It's an exhaustive list of questions, and the brokers certainly have the clearest sense of the marketplace—takeup rates, price and availability.”

This fall's congressional elections will determine next year's congressional agenda, some observers say.

The elections could have an “epic impact on the agenda,” said Mr. McKay. Republicans could gain the House majority, he said. “The Senate won't switch but should tighten up. If Republicans pick up three Senate seats and 41 House seats, I think that the administration's agenda is dead,” he said.

Not only would a switch in power change who sets the agenda, but the makeup of that majority would be different given the Tea Party movement, he said.

“I think everybody in the business community is looking to the fall elections as a bit of referendum on the role of government in the private marketplace,” said Ms. Pusey. “If polls are right, there's a bit of backlash to government spending.”

Given current conditions, “it seems very likely the elections will produce close margins in both the House and Senate, ensuring balanced and hearty debate over critical issues before Congress,” she said.