It’s election day in the U.K.

If you’ve never had the pleasure of watching British election returns come in overnight, and it usually is an all-night affair for American observers, it’s a treat. Monitoring BBC and/or Sky anchors as the Swingometer tilts gradually in one direction or another, and watching an MP accept his or her constituency’s vote of confidence on a stage alongside the costumed lunatics who also ran for the honor of occupying a seat in Parliament, is a unique quinquennial pleasure.

This year, the polls look particularly tight. The coalition government led by the Tories is in jeopardy, and British voters are in a restless mood. Political observers suspect that the Labour Party that had fallen out of favor when former Prime Minister Tony Blair left office and was replaced by Gordon Brown may be rehabilitated enough to lead a new coalition.

The polls reveal few clues as to which party will emerge victorious tonight. Labour, which had been favored in a number of early surveys, has lost some of that early momentum and now polls relatively even with the conservatives. The nationalist party UKIP has seen a spike in popularity in recent years, but it’s unclear just how many seats it can secure. After failing to win independence in a referendum last year, the Scottish National Party has rebounded in popularity. That party might also play a major role in a new coalition government.

Confused? Have no fear. Bloomberg Business has a handy 90-second video explaining this election, the political landscape, and how the British electoral system works.

“Britain needs a decisive first to avoid a constitutional crisis. If the Conservative Party finishes first – but even with their Liberal Democrat allies cannot command a majority in the House of Commons – they plan to campaign that a Labour party minority government, backed by the SNP with whom they could command a majority of votes, would be illegitimate,” Politico’s Ben Judah observed.

A lack of a decisive winner will likely lead to one of three unstable scenarios: David Cameron refusing to leave Number 10, maybe backed up by the Liberal Democrats, as his party finishes first but is unable to command a majority; Labour, reliant on SNP votes, trying to form a government but being mercilessly hounded for illegitimacy by the right leaning press; Or finally, the prospect of a second election.

This week, the influential British newspaper The Independent backed the prospect of another coalition government led by Conservatives and supported by Liberal Democrats. The paper called the idea of a coalition led by Labour dependent on the support of SNP for legitimacy a “disaster for the country.”

“For all its faults, another Lib-Con coalition would both prolong recovery and give our kingdom a better chance of continued existence,” The Independent‘s editorial board averred.

This is sure to be a tight election and one to watch. For those who are interested in following the results live, the polls in Britain close at 5 p.m. ET.