Rishi Sunak's campaign route suggests a defensive approach to fight off Labour and Lib Dems

The prime minister has taken a defensive approach, signalling the Conservatives' worry about being so far behind in the polls.

Sir Keir Starmer's visits show the scale of their ambition and highlight Labour's awareness of the challenge they face. They need to gain 125 seats to win the smallest possible majority.

This campaign is being fought on new electoral boundaries, with many constituencies undergoing significant changes since 2019.

For the purposes of this analysis, we use notional results based on calculations by Colin Rallings and Michael Thrasher, honorary professors at the University of Exeter, which estimate the 2019 election seat results if they had taken place on the new constituency boundaries.

Defending deep into Tory territory

Rishi Sunak's very first campaign stop was Erewash in the East Midlands, a seat that should be considered safe with its 22% Conservative majority, but one he clearly thinks could be vulnerable.

A Labour victory here would be at the cusp between Labour becoming the largest party in a hung parliament or taking an overall majority, if similar levels of voter swing were replicated at a national level.

The last time Labour held Erewash (which has not undergone boundary changes in this cycle) was from 1997 to 2010, under Tony Blair and Gordon Brown's leaderships.

Labour ambitious

Labour's visit to nearby Derbyshire Mid in the East Midlands shows the scale of their boldness. They need more than a 16-point swing to take the seat from the Tories, but their recent mayoral wins might mean they are feeling confident about convincing the voters here.

These stops in the Midlands show the regions to be a key battleground between the two main parties. The Conservatives had 76 MPs across the East and West, so it's crucial for their general election fortunes. The extent of Labour success here could be the difference between them being the largest party or gaining a decisive majority.

The range of seats visited by Sir Keir demonstrate just how ambitious Labour are in their targets. They aren’t shying away from places with big Conservative majorities, and kicking off their campaign in Kent tells us they think they can win in regions only Blair managed to conquer.

Reform threat

Tory troubles in Kent could also be complicated by the challenge of Reform. In Dover and Deal - where the Conservative Natalie Elphicke defected from Con to Lab - leader Richard Tice focused on immigration. The decision of Reform's honorary president Nigel Farage not to stand as a candidate in this election was one piece of good news for the Conservatives, at least.

In total, 16 of Mr Sunak’s 18 trips were to seats that the Conservatives are defending, 11 of which are vulnerable to Labour based on current polling estimates which suggest a swing of 16 points.

But that hasn't stopped Sunak trying to defend what some might think is now beyond defensible. The most marginal seat he's visited so far is Vale of Glamorgan, where he took a trip to a brewery in Barry. Labour only requires a swing of 2.6 points to win this seat, so it seems like an optimistic majority to defend.

Interestingly for a leader under pressure with many constituencies to defend, Sunak found time for a trip to Belfast East, where the Conservatives don't field a candidate. Both were part of his opening gambit of a whistle-stop tour of all the four nations to present a prime ministerial image.

Lib-Dem southern front

The prime minister is also having to fight on two fronts - with the Liberal Democrats closing in on several seats across the South of England. He visited four key Lib Dem targets, including Chesham and Amersham which has recently had a Liberal Democrat MP for the first time due to their resounding 2021 by-election victory.

There are 65 seats across the South West and South East where the Conservatives' closest challengers are the Liberal Democrats. All nine of the seats Ed Davey has been to are areas where the Lib Dems came second in 2019. And all in places that swung towards the Lib Dems in 2019 or which they held before their electoral collapse in 2015.

Davey first went to Eastbourne and enjoyed an ice cream in a key target seat where they need a 2.1 point swing to beat the Conservative candidate. He launched his Yellow Hammer 1 battle bus from Cambridgeshire South, and on Thursday he went on a waterslide in Frome & East Somerton, the constituency that will replace Somerton & Frome that they won in a 2023 by-election. That's the kind of success they will be looking to replicate and the Tories will be hoping to avoid.

Labour's eyes on the prize

Eight Conservative defended seats have had the pleasure of a visit from Sir Keir Starmer, but he has also found time to venture into SNP territory in Scotland. Why? Well Labour are also taking aim at John Swinney and his party's troubles.

Every seat Labour can win off the SNP in Scotland reduces the number they need from the Tories directly in England and Wales for a majority.

The Glasgow constituencies that were once dominated by Labour are key battlegrounds. So, unsurprisingly, the Labour leader chose to head to Glasgow East. This has had significant boundary changes, resulting in an estimated 15% majority for the SNP.

Scottish strategies

The new SNP leader Mr Swinney launched their campaign from Edinburgh, where they hold three of the five seats around the Scottish capital city. Some polling suggests Labour might take all three at this election.

He also visited Dumfries, an area served by two constituencies that the SNP hope to take from the Conservatives. They need swings of under five percentage points to do so. Scottish Secretary Alister Jack's decision to stand down in Dumfries and Galloway may suggest he thinks the Tories' prospects of defending it are slim.

While there are few Labour seats many would argue are vulnerable, the party still has its defensive issues - one of which is arguably the Greens.

They kicked off their campaign in Bristol where they are hoping to have some success in the election.

Voting patterns in recent local elections indicate that they could take up to three of the five constituencies in the area, all of which were won by Labour in 2019.

Dr Hannah Bunting is a Sky News elections analyst and Co-director of The Elections Centre at the University of Exeter.

The Data and Forensics team is a multi-skilled unit dedicated to providing transparent journalism from Sky News. We gather, analyse and visualise data to tell data-driven stories. We combine traditional reporting skills with advanced analysis of satellite images, social media and other open source information. Through multimedia storytelling we aim to better explain the world while also showing how our journalism is done.