[10][11] Shanks was an unsuccessful candidate in the 2012 Glasgow City Council election,[12] standing for Scottish Labour in the ward of Partick West and finishing fifth in the single transferable vote process.

He came third with 21% of the vote behind the incumbent SNP MSP, Sandra White, and the Scottish Greens, candidate Patrick Harvie.

[16][17][18] Shanks contested Glasgow North West at the snap 2017 general election, coming second with 35.9% of the vote behind the incumbent SNP MP Carol Monaghan.

[24] In the subsequent by-election on 5 October, Shanks was elected to Parliament as MP for Rutherglen and Hamilton West with 58.6% of the vote and a majority of 9,446.

[25][26][27][28] Prior to his election to Parliament, Shanks "said that he wasn't 'against' rejoining the EU and insisted he has not changed his principles over Brexit but that now was not the right time for a debate on the issue".

[39] Shanks described it as an "adventure" as opposed to a fitness challenge and completed it on 5 January 2022, when he ran down the city centre's George Square, which he had saved for last.