One way of getting around the disadvantages of the Two-Round System (TRS) is to merge the first and second round into one election. There are several ways of doing this. The most straightforward adaptation is the preferential system used for presidential elections in Sri Lanka (see the Sri Lankan case study Sri Lanka: Changes to Accommodate Diversity). There, voters are asked to mark not only their first choice candidate, but also (if they wish) their second or third choices by placing the numbers '1', '2' and '3' next to the names of the candidates, in the same manner as the Alternative Vote (see Alternative Vote) and the Single Transferable Vote (see Single Transferable Vote) described earlier. If a candidate gains an absolute majority of first preference votes, they are immediately declared elected. However, if no candidate gains an absolute majority, all candidates other than the top two are eliminated, and their second or third choice votes are passed on to one or the other of the two leading candidates, according to the preference ordering marked. Whoever achieves the highest number of votes at the end of this process is declared elected. This system thus achieves in one election what TRS achieves in two, with significant cost savings and greater administrative efficiency.
The disadvantages of the Sri Lankan system include:
- the literacy requirements common to all preferential voting systems, and
- the fact that voters are effectively required to guess who the top two candidates will be in order to make full use of their vote.
This is not a disadvantage of the Alternative Vote (AV), which is used to elect the Irish President (see Ireland: The Archetypal Single Transferable Vote System). The procedure for marking the ballot is virtually identical to the Sri Lankan case, with the exception that Irish voters can mark as many preferences as they wish, and are not restricted to three as is the case in Sri Lanka. But the way the votes are counted is quite different. Instead of simultaneously eliminating all but the top two candidates, under the Alternative Vote the lowest-placed candidate is eliminated, and the corresponding votes transferred according to their next preference. This process is repeated until one candidate has an overall majority, or until all preferences have been counted. Unlike the Sri Lankan case, under Irish AV a lower-placed candidate who picks up lots of preference votes can still overtake higher-placed candidates and ultimately win the seat. The most recent example of a president winning through the transfer of preferences in this manner was the 1990 election of Mary Robinson to the Irish Presidency.
Despite these differences, both systems have the same core aim: to make sure that whoever wins the election will have the support of the majority of the electorate. The use of preference votes to express a second choice means that a second round of voting is not required, and this results in significant cost savings, as well as benefits in administrative, logistics, and security terms.
