The Prime Minister, David Cameron, is on a bit of a tour of the British car industry at the moment - with an election looming, this is an industry with which he wants to be associated.

Today he started with a trip to Rolls-Royce - fresh from its confirmation that it will build a 4x4 - prior to moving on to Vauxhall and Cosworth, both of whom are taking on more workers as business booms.

It's always fascinating to watch top politicians at work. Cameron talked for more than an hour at Rolls-Royce, giving a five-minute opener before turning it in to a town hall-style question and answer session with the workers.

He tackled everything from the threat from Islamic State to his desire to grow apprenticeships by half again if he's re-elected and to push for more job-focused technical colleges to be built. That and humorous exchanges about his beloved Aston Villa and one worker's disappointment that DC hadn't turned out to be David Coulthard.

For car lovers the message was clear: the industry cherishes all that makes an economy strong, and it will therefore be backed to the hilt. Investment in people and places, design, manufacturing, engineering and research and development leads to exports, sales and growth. It's a heady mix for a politician.