NEW YORK -- US presidential elections routinely hold a global audience, with onlookers from around the world hooked on the theatre of the campaigns, the stage-managed debates and the tense denouement of election night.
In comparison, the midterm elections - held every four years (at the mid-point between presidential elections) - are far more perfunctory, comprising regional battles in which members the Senate and the House of Representatives are elected to Congress.
Yet the midterms are absolutely vital in shaping US domestic and foreign policy for years to come, with the makeup of the Congress determining how much of the current and future president's agenda can be pushed through - whoever he or she is.
This November, Americans (or around 40% of those eligible to vote) will head to the polls, with one race in particular likely to have a huge impact, not just on the US but around the globe.
Welcome to the senatorial race of Kentucky, a state better known for Bourbon, horse racing and boxes of chicken, yet the scene of an election that could sharply define America's approach to climate change for the foreseeable future.
Climate policy in the US has gained significant traction in recent years, with all but the most industry-tied politicians reluctant to deny the phenomenon, such is the weight of scientific consensus (many Republicans instead refuse to commit by saying "I don't know, I'm not a scientist").
A bi-partisan report published in June detailed the huge costs to American business of refusing to act and, though Obama has failed to pass broad legislation to counter rising temperatures, he has, through the use of an executive action, pushed through a Clean Power Plan, setting limitations on how much carbon can be emitted into the atmosphere by the country's power plants.
Senate Minority Leader Mitch McConnell speaks to supporters during a bus tour of Kentucky on August 7 (Getty Photo/Win McNamee)
Tasked with enforcing this plan is the Environmental Protection Agency (EPA), a body much maligned by the Republicans and the corporate interests they dutifully serve. Yet left in place, the Clean Power Plan is likely to have a significant impact on reducing pollutants in the atmosphere - down 17% from 2005 levels by 2020.
Enter Mitch McConnell, Kentucky's incumbent senator who has spent the past 30 years in Washington working on behalf of America's coal industry. Should he retain his seat next month, the ageing politician is likely to become the Republican majority leader in the Senate - and the man charged with ensuring the final two years of Obama's presidency are as uncomfortable as possible.
Republicans would also have to triumph in other states, with close races in South Dakota, Kansas and Georgia but, should McConnell become majority leader, he has already promised to roll back the emission caps, hobbling America's fight against climate change for years to come.
Standing in his way is 35-year-old Alison Lundergan Grimes, the Democratic Party challenger, who is currently polling level with her more experienced opponent. Most commenters think McConnell has the edge, but the vote could go either way.
So how could the leader of the biggest party in the Senate stop the President reducing carbon emissions? The answer is indirectly. Obama would veto any direct attack on his policy, so instead McConnell plans to place restrictions on the EPA within routine budget bills, with any veto from the White House carrying the risk of shutting down the government.
McConnell was caught on tape outlining this strategy at an event for wealthy Republican donors in August. He said: "So in the House and Senate, we own the budget. So what does that mean? That means that we can pass the spending bill.
"And I assure you that in the spending bill, we will be pushing back against this bureaucracy by doing what's called placing riders in the bill. No money can be spent to do this or to do that. We're going to go after them on healthcare, on financial services, on the Environmental Protection Agency, across the board."
In short, McConnell could make Obama choose between shutting down the government and compromising on climate change policy. And with 10 of the hottest years on record occurring in the last 16 years, neither America nor the world has time to allow McConnell to force compromise.