the Conservatives fell to 2,798 votes and the Labour share dipped below 50%. The same year saw the Scottish National Party contest the seat in a general election for the first time, though they had previously contested the 1952 by-election. The constituency has been a marginal seat between the SNP and Labour since the 1973 by-election. Although Labour won the seat in that by-election, the SNP established itself as the clear challenger and continued to advance, winning the seat in the next general election. Labour were thought to have underperformed in not winning the seat back in the 1979 general election, and the choice of the former Communist Jimmy Reid as Labour candidate was blamed for the loss. John McAllion regained the constituency for Labour at the 1987 general election. Boundary changes which came into force in 2005 brought in many voters from more suburban areas formerly in the Angus constituency. Although estimates of the 2001 general election result on the new boundaries showed Labour ahead, the lead was exceptionally narrow, and after the SNP won the Scottish Parliament seat on the original boundaries in 2003, a close fight was expected (and occurred) in the 2005 general election. The constituency was gained by the SNP's Stewart Hosie, who won the constituency with a 1.0% vote majority ahead of Labour in 2005, which he increased to 4.5% at the 2010 general election. In 2015, the sitting SNP MP Stewart Hosie retained the seat with a majority of 19,162 votes and a 39.8% share of the vote. This was the largest majority of any of the 56 SNP MPs elected at that year's general election in terms of percentage, although a slightly larger numerical majority was achieved in Falkirk. In 2017 Hosie's vote share dropped to 42.8% and a revived Conservative Party cut his majority by more than two thirds to 6,645. Labour narrowly slipped into third place. In 2019 Hosie increased his majority to over 13,000 votes as his vote share rose by 11%. In percentage terms, the SNP majority of 29.54%, was the party's second largest at the election, being surpassed only by the 33.87 majority it had in Aberdeen North. The Conservative's remained in second place with a small decrease in vote share, but the Labour vote decreased dramatically as the party recorded its worst ever result in the seat's history. Members of Parliament Election results Elections in the