Over the last seven years, the President and Congress have waged a number of battles over key pieces of legislation. In some cases, Congress has attempted to roll back or overturn policies and laws through votes in the House and Senate, and, in almost all cases, they have been unsuccessful. We could be on the verge of another battle.

On the very day the U.S. Environmental Protection Agency (EPA) published the final rules for the President-backed Clean Power Plan in mid-October, 26 states along with coal companies and industry groups launched a legal challenge to the plan. Wheels are already in motion among certain members of Congress to try and overturn the rule.

The key question for those on both sides of the debate is: “What is the most likely outcome of these challenges?” While the legal challenges will take years to play out in courts and are much harder to predict, we can make some educated observations about congressional attempts to overturn the Clean Power Plan based on history and precedent. Let’s take a look at three strategies that are unlikely to overturn the Clean Power Plan, and why they still matter.

The Congressional Review Act and the Role of Veto Power

Some members of Congress have already challenged the plan under the Congressional Review Act (CRA). Earlier this week, the House passed the CRA disapproval resolutions, following the Senate’s passage last month, which received the support of three coal-state Democrats. Enacted in 1996, the CRA enables Congress to overturn a ruling by the executive branch with majority vote in the Senate. But in its nearly two decades in existence, the CRA has only been successful once. It’s an unsurprising track record when you consider that overturning a rule under the CRA requires Presidential sign-off. In this case, it would require the President to overturn rules that he has aggressively pushed through. Unlikely even in an ordinary set of circumstances, such a reversal is especially improbable in the current political climate.

The Budget Approval Stand-Off

Funding is at the heart of most political debates, and the Clean Power Plan is no exception. As a federally-funded agency, the EPA works within an operational budget determined by the annual congressional appropriations bill. Congress has the power to condition the use of government funds and in this case, policy riders could be applied to prevent the EPA from using government money to enforce the plan. This would mean the rule would technically remain in effect, but enforcement would be impossible.

Congress has attempted this tactic a few times in the recent past and has fallen short in each instance because, ultimately, the government requires an approved budget to continue operating. Allowing the government to shut down for the sake of opposing a single rule – no matter how ardent that opposition – has severe consequence, not to mention is generally unpopular among the constituents of elected officials. At the end of the day, with the current continuing resolution set to expire on December 11, Republicans may end up including other energy-related policy riders in a final funding bill, in hopes of winning less-controversial energy priorities.

Politics Today and Politics Tomorrow

The current president, arguably the most important proponent of the Clean Power Plan, has entered the last 12 months of his presidency. Next year’s presidential election could give the country a vastly different political landscape. Under new presidential leadership, and depending on what happens in Congress, there may be more sympathy towards overturning the plan. However, at that point, the rule will have been in effect for more than a year. The EPA would be permitted the opportunity to alter elements of the rule, and the public would be allowed to weigh in, before the rule could go to Congress for a vote. Approval in both the House and Senate would be needed to pass legislation overturning the rule, and political support for such a reversal among Democrats would likely be very low.

The Long View

As explored above, there are a number of reasons why opposition to the Clean Power Plan is unlikely to result in its dismissal. But history shows us that continued political pressure can have an effect on future legislation. These strategies will bring more public attention to the issue and may very well influence public discourse on the plan’s rules. It will also force representatives to take an on-the-record stand on the issue. In the world of politics, voting records can have a significant impact on future election cycles. With a little more than two full years until compliance plans must be submitted under the Clean Power Plan, and more than six years until compliance will be enforced, there is still time for this rule to evolve. Both its final form and its very existence could change based on how the above strategies impact public opinion.