The seat became vacant following the death of the constituency's Member of Parliament, James Haslam on 31 July 1913. Haslam had been the MP here since 1906. He was the Secretary of the Derbyshire Miners' Association who acted as his sponsor. He had been first elected to the seat as a Liberal or Lib-Lab candidate and once in parliament, took the Liberal whip. Following a decision of the Miners Federation of Great Britain to affiliate to the Labour Party, all miners sponsored MPs were requested to take the Labour whip and contest the following election as a Labour Party candidate. Haslam complied with this request and at both the January and December 1910 General Elections was re-elected as a Labour Party candidate without facing a Liberal opponent.
Kenyon was a long-standing official of the Derbyshire Miners' Federation. When James Haslam announced in 1912 that he would not be standing again the Miners decided to nominate Kenyon to succeed him. Haslam died on 30 July 1913 creating a vacancy and a by-election. Although the Liberals had not opposed Haslam in 1906 or in either of the two general elections of 1910 they decided they would contest the next election and had earlier adopted Alderman George Eastwood, the President of Chesterfield Division Liberal Association. The Unionists adopted Edward Christie of Hendon and the Derbyshire Miners selected Barnet Kenyon, then treasurer of their Association and one of its most popular officials to be the Labour candidate. Kenyon's politics however can best be described as Lib-Lab and when Alderman Eastwood declined the Liberal nomination having been taken ill Kenyon soon agreed to be adopted officially by the Liberals too. This decision soon proved problematic for the Miners Federation and for the Labour and Liberal parties. The position was to be referred to the Miners' Federation of Great Britain and the Derbyshire Miners' Association. This apparent return to outright Lib-Labbery was resented by the socialists who appealed to Labour headquarters to intervene. The outcome was expected to be that if the position could not be resolved, Labour would seek to adopt a new candidate to oppose Kenyon.
By 8 August, the Liberals were attempting a compromise, saying they would not formally adopt Kenyon but would rely on his nomination as the Miners’ candidate in the expectation he would take the Liberal whip once elected to Parliament. In return he would be known as the Labour-Progressive member and would have full freedom to speak and vote as he wished on issues affecting mining and labour. This was seen as a climb down by many Liberals to avoid the possibility of the national Labour party putting up a rival candidate. Despite an attack on Kenyon’s conduct in regard to the nomination for the by-election in the publication Labour Leader, Labour Party headquarters in London was reported to be satisfied with the Liberal Party compromise position, and at this point Ramsay MacDonald announced he would support Kenyon's candidacy. A few days later, Kenyon was being described as the 'Liberal and Labour' candidate in the press but many Liberals in Chesterfield were unhappy at the way he seemed to be ignoring the Liberal side of his programme in favour of labour and mining issues and was apparently refusing to use the word Liberal in his campaign or at his election meetings.
An issue which had a direct impact on the election was the working of the National Insurance Act of 1911, which came into effect in 1913. This legislation was a key component of the social reforms introduced by the Liberal government after 1908 which also included the first Old Age Pensions. The Act covered sickness, invalidity and unemployment benefits and brought real improvement in getting access to a doctor for poorer patients. However, regulations which the Insurance Commissioners (the body of civil servants responsible for administering the legislation) had introduced were believed to be adversely affecting many patients. The government had decided not to treat medical associations which were friendly societies in the same way as panel doctors, i.e. doctors agreeing to treat patients under the provisions of the Act. Most doctors who took panel patients also continued to treat private patients who paid their own costs. The panel system did not however operate in Chesterfield where the medical association performed a similar role. The decision not to put the association on an equal footing with panel doctors must have seemed to those who had insured themselves against sickness through their medical associations, a deliberate attempt to penalise the friendly societies. It could also have been viewed as an attack on the traditional Liberal concept of self-help. The Chesterfield Medical Association, a local friendly society, which was variously reported to have had 4,000 or 7,000 members many of whom were Liberal voters, were incensed at the new regulations. There was even a realistic prospect of an independent candidate being put up to fight on the health insurance issue, although negotiation with government to gain concessions was preferred and a meeting was hastily arranged at the House of Commons between a deputation from the Chesterfield Medical Association and Lloyd George the Chancellor of the Exchequer and the Financial Secretary to the Treasury Charles Masterman. While the threat of an independent medical association candidate receded, resentment remained high and the association members were urged not to vote for Kenyon.
Despite their earlier willingness to accept Kenyon as the Labour representative, the executive committee of the national Labour party at a meeting at their Victoria Street headquarters in London passed a resolution on 12 August 1913 repudiating Kenyon as an official Labour candidate on the grounds that he was not conducting his campaign in accordance with the Labour Party constitution. This decision caused some disquiet to Labour supporters of Kenyon in the constituency as it now seemed distinctly possible that an official Labour candidate would be put up. They were right to be concerned because on 14 August, just two days before close of nominations, a meeting of trade unionists and socialists in Chesterfield voted to put up John Scurr, Chairman of the London District Committee, Dock, Wharf, Riverside and General Labourers' Union to be Labour and Socialist candidate at the by-election. Scurr had fought a Parliamentary election as a socialist before, at South West Bethnal Green in 1911 where he came bottom of the poll by a long margin. He was to contest the same seat again in 1914 and he also fought at Ipswich in 1914. Scurr later became an Alderman on Poplar Borough Council and was imprisoned in the controversial rates case there in the 1920s. He later won a seat on the London County Council and became Labour MP for Mile End.