Theresa May's visit to Wolverhampton last Saturday spoke volumes about the Conservatives emerging electoral strategy. Following their high-profile Mayoral win in the West Midlands and a strong local election performance across the rest of the country, the question is increasingly not whether May remains Prime Minister, but just how big a majority over Labour the Conservatives will get.

If the Conservatives are going to get close to the 418 seats won by Labour under Tony Blair in 1997, they will need to win in seats where since the late 1980s and early 1990s, they have failed to make an impression. One such area is the West Midlands conurbation, where in 1983 and 1987 the Conservatives polled more votes than Labour and won only marginally fewer seats. Since then, Labour has dominated, but in 2017 Conservative hopes of a revival look realistic. Eleven Labour-held seats in the West Midlands conurbation area require a direct swing of around nine per cent or less from Labour to Conservative to go blue. In six of these seats, the margin between the Labour incumbent and the Conservative challenger is ten per cent or less.

There are many reasons why Labour should be worried. Prior to the local elections, we showed using survey evidence from the British Election study that of those who were defecting from UKIP, around three-quarters in Conservative-Labour marginals were switching to the Conservatives. This realignment on the right was borne out in the local elections last Thursday with a 'blue wall' of Conservative support proving impenetrable for all parties including Labour up and down the country. The make-up of this Conservative vote seems extremely solid with traditional Conservative 'Leave' voters being joined by 2015 UKIP supporters many of whom originally defected from both the major parties. This is reinforced by the reluctance of Conservative 'Remainers' to jump ship with many accepting the 'Brexit' outcome and recognising the need for 'stable and strong' leadership during 'Brexit' negotiations. Here Corbyn scores badly when compared with May, particularly in terms of competence, while party division adds to Labour woes.

Another reason is direct switching from Labour to the Conservatives. Flow of the vote figures from the British Election study suggest that on average five per cent or more of 2015 Labour voters seem intent on pledging support to the Conservatives in 2017. Although ICM polling figures released yesterday suggest that this could be as much as 12 per cent. More worrying for Labour is the uncertainty of its traditional Labour core. Of those who voted Labour in 2010, nearly 1 in 5 has shifted to either the Conservatives or UKIP with half remaining loyal to Labour. But a quarter remains undecided about how they will vote in 2017. Three-quarters of these undecided 2010 Labour voters supported Labour last time. But they seem detached from Corbyn's Labour Party expressing lower levels of partisanship, dislike for Labour and their leader as well as concerns around the cultural threat of immigration when compared to those who say they will remain loyal to Labour in June.

Keeping this core vote together in seats across the West Midlands conurbation is vital if the party is to withstand the Conservatives' offensive push. If not, Labour risk losing both Walsall seats, two of the seats in Wolverhampton and Coventry alongside reversals across Birmingham. Both Northfield and Edgbaston could fall but Erdington looks to be a good barometer for the election. In 1983, Robin Corbett won the seat by 231 votes from the Conservatives, while the seat itself notwithstanding redistricting has not turned blue since 1936. If this happened, then Labour would undoubtedly record its lowest level of parliamentary representation since the 1930s and May would be on the verge of matching Blair’s majority in 1997. But if Labour can turn the tide across the West Midlands in those seats where core Labour voters are a similar demographic to those in Labour strongholds elsewhere in the country, then the seat gap between the two parties might not turn out to be as large as current polling suggests. That's why what happens in the West Midlands will tell us a lot about the outcome on 08 June 2017.

Professor David Cutts
Professor of Political Science, Department of Political Science and International Studies