Rep. Todd Akin (R-MO) captured the attention of election spectators across the nation when he asserted that a woman's body could avoid pregnancy by "shutting the whole thing down" in the case of "legitimate rape." Leading Republicans, including the party's presumptive presidential nominee Mitt Romney, have called on him to step down as the Republican nominee for U.S. Senate in Missouri. As the country raises its brow and wags a finger in Akin's direction, many have wondered how such a candidate came to office in the first place. 

I make no judgment about Akin's alleged extremism. This month he won a major party's nomination for a highly competitive Senate seat and he is finishing his sixth term in the U.S. House, having won most of his previous elections by lopsided margins. But given the controversy over his nomination and his long history of being seen as particularly conservative on social issues, it's instructive to see how our electoral rules may have contributed to his political success.

A sparsely publicized fact is that the majority of voters rejected Akin as their choice candidate in his first primary bid for Congress. In 2000, Akin narrowly won by 293 votes, securing only 26% of the primary electorate's support against 74% of the vote split among other candidates. His closest competitors Gene McNary and Francis Flotron received 26% and 22% of the vote respectively, resulting in no majority for a single candidate.

After securing his first nomination, Akin never again faced a tough primary - the usual norm for incumbents, particularly if they haven't disappointed highly partisan voters in their party. In the general election, Akin represented a solidly Republican district, which again is typical of incumbents due to how most parts of the nation lean clearly toward one party or other. (See our assessment of Akin's district and all other congressional districts at FairVote's new Monopoly Politics 2012 report summarized with an interactive map).

In 2012, Republicans saw a great opportunity to pick up Missouri's U.S. Senate seat. Although historically a swing state, it now leans Republican - and first-term incumbent Claire McCaskill is seen as vulnerable. Several Republicans sought the nomination. Just as in Akin's 2000 primary, far short of the majority of Missouri Republicans supported Akin in the primary. Receiving a plurality of 36%, Akin advanced as the Republican candidate for senate despite being opposed by 64% of the electorate - including challengers who won 30% of the vote and 29% of the vote, respectively. Observers suggest that McCaskill tried to boost Akin, who was thought to be the easier cadidate to beat the general election, by running $2 million in ads for him, aware that doing so would strengthen his support among conservative Republicans. 

Missouri's voting law made such a strategy all the more effective. Candidates lacking majority support often fill our elected offices due to plurality voting, a system where the candidate who receives the most votes in an election wins. Plurality voting affects who runs in a race and who wins it. On the one hand, potential candidates are often discouraged from joining plurality races due to the spoiler effect, which occurs when the vote is split between two like-minded candidates allowing a less desirable candidate to win. On the other hand, when more than two candidates run - as is common in primary races where the winner will be favored in November - you can get winners who would have been unlikely to secure a majority of the vote in a one-on-one race.

FairVote opposes plurality voting for both of these reasons: we believe voters should have real choices, but we don't believe having those choices should lead to unrepresentative winners. Because we cannot be satisfied with structures that impede democratic principles such as majority rule, reform of plurality voting is necessary to advance the franchise of the individual and the will of the majority.

When electing single winners in governmental elections around the world, only three systems are used: plurality voting and two systems that would avoid its problems of split votes and undemocratic outcomes. Used for most presidential elections around the world and in primaries in several states, the most common alternative method is to require the top two finishers in the first round to face off in a runoff if no candidate has won a majority. Runoff elections have three big advantages over plurality voting: candidates must demonstrate substantial support among voters, voters in the first round have much less concern about splitting the vote and voters get a "second look" at candidates.

Instant runoff voting, a ranked choice voting method, is the other alternative to plurality voting that has gained growing support. Used to elect offices such as the president of Ireland, parliament of Australia and mayors of London (UK), Minneapolis (MN), Portland (ME) and San Francisco (CA), IRV allows voters to indicate their compromise choices along with their first choice by ranking candidates in order of preference. IRV does an even better job than runoffs in avoiding "spoiler": concerns, requires candidates to reach out to more voters to win and avoids some of the downsides of traditional runoffs such as extra campaign finance burdens, declines in voter turnout between rounds and highly negative campaigns.

Reforming plurality voting creates an opportunity to improve our democratic system by ensuring a candidate doesn't win just because the majority splits its votes among other candidates. Whether Akin would have won a majority vote in a runoff election or under IRV is unclear. That ambivalence should provoke a national conversation about whether we should uphold the plurality system. As a nation founded upon democratic principles, we must ensure that our elections appoint the candidate who best represents the goals of the electorate.