兩黨制

兩黨制 (英文：Two-party system) 係一種政黨嘅制度，由兩個黨包攬哂啲選舉同議會。喺呢個制度入面，一般一個會做執政黨，而另外嗰個就會做反對黨。呢個字眼可以有唔同嘅含義，不過最普遍都係講緊個地方嘅政治由兩個黨自己玩，好少能夠有第三個黨贏到任何嘢。

原因

呢個制度可以有好多原因，其中最常見就係單議席單票制或者領先者當選（英文：First-past-the-post voting），令選票自然集中入是但一個黨度嚟令贏嘅機會最高^[1]^[2]。

政治學家對於點解一個自由選舉，好多時會自然演變做兩黨制有唔同嘅見解。其中一個好普遍嘅解釋就係 Duverger's law（英文：Duverger's law），解釋點解領先者當選（英文：First-past-the-post voting）嘅制度會搞到啲選舉剩返兩個黨^[3]。

特徵

喺呢種制度，第三黨贏嘅機會少到近乎冇，所以好多時如果出現分歧，就會係喺黨入面嘅派系^[4]^[5]。一般嚟講，因為個制度得兩個黨，所以一個會係左派，另一個會係右派，嚟代表到最多人嘅意識形態。例子有美國嘅民主黨（左）同埋共和黨（右）、英國嘅工黨（左）同埋保守黨（右）、同埋澳洲嘅工黨（左）同埋自由黨（右）。

喺有啲國家，例如加拿大、英國、或者澳洲，個政黨嘅制度冇兩黨制咁極端，不過就係由兩個黨控制大部分，仍然會有其他細嘅黨贏到議席，只不過唔會可以做執政黨咁解。喺呢啲國家，細黨嘅候選人仍然能夠贏到地區嘅選舉，只係贏唔到比較大型嘅全國選舉^[6]。

睇埋

攷

↑ Two-party systems are prominent in various countries, such as the U.S., and contain both advantages and disadvantages. Boundless Publishing. 原著喺2013-10-03歸檔.
↑ Black, Eric (2020-05-02). Why the same two parties dominate our two-party system. Minnpost. 原著喺2020-05-02歸檔.
↑ Fey, Mark (2007). "Duverger's Law Without Strategic Voting" (PDF). University of Rochester.
↑ Bashan, Patrick (2004-06-09). "Do Electoral Systems Affect Government Size?". CATO Institute. 原著喺2020-03-10歸檔.
↑ Chris Cillizza and Aaron Blake, May 18, 2012, The Washington Post, Americans Elect and the death of the third party movement 互聯網檔案館嘅歸檔，歸檔日期2020-02-25., Accessed August 11, 2013
↑ Disch, Lisa Jane (2002). The Tyranny of the Two-Party System. Columbia University Press. ISBN 978-0231110358. 原先內容歸檔喺2011-12-26. 喺2012-10-29搵到 –透過Google Books.

[Boundless-1] Two-party systems are prominent in various countries, such as the U.S., and contain both advantages and disadvantages. Boundless Publishing. 原著喺2013-10-03歸檔.

[EricBlack-2] Black, Eric (2020-05-02). Why the same two parties dominate our two-party system. Minnpost. 原著喺2020-05-02歸檔.

[3] Fey, Mark (2007). "Duverger's Law Without Strategic Voting" (PDF). University of Rochester.

[Cato-4] Bashan, Patrick (2004-06-09). "Do Electoral Systems Affect Government Size?". CATO Institute. 原著喺2020-03-10歸檔.

[Cillizza2-5] Chris Cillizza and Aaron Blake, May 18, 2012, The Washington Post, Americans Elect and the death of the third party movement 互聯網檔案館嘅歸檔，歸檔日期2020-02-25., Accessed August 11, 2013

[6] Disch, Lisa Jane (2002). The Tyranny of the Two-Party System. Columbia University Press. ISBN 978-0231110358. 原先內容歸檔喺2011-12-26. 喺2012-10-29搵到 –透過Google Books.

[1]

[2]

[3]

[4]

[5]

[6]