Two-round system

[1][4] Despite this, runoff-based rules like the two-round system and RCV have faced criticism from social choice theorists as a result of their susceptibility to center squeeze (a kind of spoiler effect favoring extremists) and problems like the no-show paradox.

Georgia, Louisiana, California, and Washington[note 2] use the two-round system for all non-presidential elections.

Mississippi uses it for state offices,[9] while Alaska and Maine use the similar ranked-choice voting (RCV) system which does not require multiple rounds.

[13][14][17] The French system of ballotage was first established as part of the reforms of the July Monarchy, with the term appearing in the Organic Decree of 2 February 1832 of the French government, which mandated a second-round election "when none of the candidates obtains an absolute majority".

[18] The rule has since gained substantial popularity in South America, Eastern Europe, and Africa, where it is now the dominant system.

In the 2002 French presidential election, the two contenders described by the media as possible winners were Jacques Chirac and Lionel Jospin, who represented the largest two political parties in France at the time.

However, 16 candidates were on the ballot, including Jean-Pierre Chevènement (5.33%) and Christiane Taubira (2.32%) from the Plural Left coalition of Jospin, who refused by excess of confidence[clarification needed] to dissuade them.

The exhaustive ballot (EB) is similar to the two-round system, but involves more rounds of voting rather than just two.

Most of the mathematical criteria by which voting methods are compared were formulated for voters with ordinal preferences.

Some methods, like approval voting, request information than cannot be unambiguously inferred from a single set of ordinal preferences.

The two-round system is such a method, because the voters are not forced to vote according to a single ordinal preference in both rounds.

At the very least, their opponent would have to start taking the so-called weak candidate seriously, particularly if the runoff follows quickly after the first round.

The intention of runoff voting is that the winning candidate will have the support of an absolute majority of voters.

The two-round system tries to overcome this problem by permitting only two candidates in the second round, so that one must receive an absolute majority of votes.

Critics argue that the absolute majority obtained by the winner of runoff voting is an artificial one.

When a Condorcet winner exists, the candidate does not necessarily win a runoff election due to insufficient support in the first round.

Runoff advocates counter[citation needed] that voters' first preference is more important than lower preferences because that is where voters are putting the most effort of decision and that, unlike Condorcet methods, runoffs require a high showing among the full field of choices in addition to a strong showing in the final head-to-head competition.

Because it encourages conciliation and negotiation in these ways, runoff voting is advocated, in various forms, by some supporters of deliberative democracy.

Therefore, like other single-seat methods, if used to elect a council or legislature it will not produce proportional representation (PR).

In Australian politics, the two-party-preferred vote (TPP or 2PP) is the result of the final round of an election or opinion poll after preferences have been distributed to the highest two candidates, who in some cases can be independents.

The TPP is an indicator of how much swing has been attained/is required to change the result, taking into consideration later preferences.

In smaller elections, such as those in assemblies or private organizations, it is sometimes possible to conduct both rounds in quick succession.

As a result, one of the most common criticisms against the two-round system is that the cost and difficulty of casting a ballot is effectively doubled.

[24] However, the system may sometimes still be cheaper than holding a ranked-choice runoff (RCV), as the counting of votes in each round is simple.

In Italy, it is used to elect mayors, but also to decide which party or coalition receives a majority bonus in city councils.