Approval Voting Is Better for both Major AND Minor Parties


We contend that Approval Voting is better for major parties and minor parties. How can this be?

Sample Election

Consider this simplified election scenario in which the major party candidates are M1 and M2, and a minor party (or independent) candidate is represented with a lowercase “m”. We'll say for the moment that these expressions are completely honest.

% of voters          their ranking
49%                    M1 > others
41%                    M2 > others
10%                    m > M2 > M1

This examples shows that 49% of the voters favor M1 over all other candidates. The remainder votes are split between M2 and m. Note that we purposely ignore certain orderings, to make the example as simple as possible. One can easily construct more realistic/complicated examples if desired.

Expected Results with Plurality Voting

As the bottom row in the previous section shows, 10% of voters prefer the minor party candidate. We assume that 30% of them (3% of the total electorate) will vote sincerely, while the rest will cast a strategic vote for M2. Studies show time and again that most voters using plurality voting will vote insincerely if their favorite candidate appears unlikely to win. Thus the result would be:

% of voters     their vote
49%               M1
48%               M2
3%                 m

Result: bad for M2 and for m and for voters

M1 wins, even though a 51% majority of the voters prefer M2 to M1. The results say that only 3% of voters supported m, when in fact m was the favorite of 10%. It incorrectly appears as though m has only about 6% as much support as either major party candidate.

Expected Results with Approval Voting

It bears reminding that approval voting always lets the voter support a sincere favorite. We realistically assume that all of m’s supporters who would have tactically voted for M2 will also vote for m with approval voting. In addition, we assume that two thirds of the voters who voted only for m with plurality voting will now also cast a strategic vote for M2, since that still allows them to express their sincere support for m.

% of voters          their vote

49%                    M1
41%                    M2
9%                     m + M2
1%                     m

Result: good for M2 and for m and for voters

M2 wins, with a combined 50% approval, compared to 49% for M1. The results correctly show that 10% of voters supported m. It’s clear that m had about 20% as much support as either major candidate, not a mere 6% as inaccurately conveyed by plurality voting.

What if Minor Parties Actually Win?

If you’re a major party incumbent or potential future candidate, you might have some reasonable concern about the possibility of losing to a minor party or independent candidate as a result of having approval voting. But thinking about the current strength of minor parties in the USA, you have to make a strategic consideration of which is more likely:

  1. Approval voting helps you by saving you from losing to your major party opponent, when you really should win, by fixing the spoiler problem.
  2. Approval voting hurts you by allowing a minor party candidate to defeat you.

At the present time, scenario #1 is much more likely in most races, meaning approval voting is a good bet.

Approval voting could allow minor parties to grow more competitive over time, and even win when the major parties become insufficiently representative. But that’s more of a problem for future politicians. By supporting approval voting today major party politicians can protect themselves, while leaving a lasting legacy of improved democracy for their constituents.

We thusly believe that savvy major party politicians will support approval voting. This is especially true for internal processes. For instance, a major party which uses approval voting for internal nominating and decision making would be at an advantage and likely win more elections.

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