Since 1922 the British electorate has returned either a Conservative or Labour Government, leading many to conclude that British politics will continue to be dominated by a two-party system. However, rising levels of public disenchantment with the major parties has seen the popularity of smaller parties, including nationalists, grow. The electoral success of the Scottish Nationalist Party in Scotland and the Liberal Democrats/Brexit Party in the last European Elections have led some to doubt whether the future of the UK's two-party system.
In recent years, smaller political parties have played an increasingly important role in UK general elections. In two out of the last four elections (2010 & 2017) a smaller party has played the role of king-maker when neither major party secured a parliamentary majority. In the recent general election in December 2019 a significant portion of voters opted to back smaller parties. Over 16% of the electorate backed a party that neither the Conservative nor the Labour Party. Aside from playing 'king-maker', smaller parties are also setting the political agenda. The Conservative and Labour Party spent a significant portion of the previous general election having to tailor their message to the electorate in response to insurgent parties. In the case of the Conservatives they were responding to the Brexit Party and attempting to win over leave voters and the Labour Party attempted to pivot in response to the Liberal Democrats who were targeting remain voters in urban metropolitan centres. Even the Green Party's policy agenda which called for new environmental measures and a 'Green New Deal' was incorporated in some form in both the major parties manifestos. The Scottish Nationalists continued domination in Scotland has reshaped politics and challenges the notion that for the whole of the UK electorate it is a straight choice between Conservatives and the Labour Party. Aside from being in government in Scotland since May 2007, the Scottish Nationalists have won a majority of the parliamentary seats in Scotland in every general election since 2015. In Scotland the picture could not be more different with the Scottish Nationalists being the main challenger verses an array of UK-wide 'union' supporting parties including Labour, the Conservatives, and the Liberal Democrats.
The influence of smaller parties is overstated and largely tied to the fact that prior to the last election neither party had obtained a significant parliamentary majority since 2005. Brexit has dominated British politics for the last three years, with simpler electoral coalitions, smaller parties were able to adopt extreme positions to mobilise leave/remain voters. While these extreme positions attracted voters in the last EU parliamentary elections and represented a significant shift in election opinion polls, the majority of voters ultimately chose to back one of the two established political parties. The Brexit Party went from at one point leading in the national polls to not gaining a single parliamentary seat. Similarly, the Liberal Democrats were at one point polling above the Labour Party, yet the party failed to make gains and leader Jo Swinson lost her seat to the Scottish Nationalists. The electoral dominance of the Scottish Nationalists is far from assured. In 2017, the Scottish Nationalists lost 21 seats and the party's national vote share at the last election was significantly less than its 2015 peak of 4.7%. Despite a strong showing in 2019, a majority of Scottish voters voted for a party that was against the Scottish Nationalists.
[P1] A significant portion of British voters will continue to support smaller parties. [P2] The Scottish Nationalists will remain dominant in Scotland. [P3] Smaller parties will continue to set the political agenda outside of Brexit. [P4] Smaller parties will continue to have a role as a 'king-maker'.
Rejecting the premises
[Rejecting P2] The Scottish Nationalists have reached an electoral ceiling in Scotland. [Rejecting P3] The Conservative's parliamentary majority ensures that they will set the policy agenda. [Rejecting P3 & P4] The Conservatives at the last election won the largest parliamentary majority since 2005, reducing the influence of smaller parties.