The surprise resignation of rising star Louise Mensch will result in a high-profile by-election that Labour is likely to win, something the Prime Minister would have been happy to avoid.
In her resignation letter Mensch said she had been “struggling for some time” to combine her role as MP for Corby with her family life since marrying Peter Mensch, manager of the band Metallica, who lives in New York.
“I am very sorry that despite my best efforts, I have been unable to make the balancing act work for our family,” she told the Prime Minister.
Cameron accepted her resignation with regret, hinting that she may have been in line for a ministerial post: “You have been a truly inspiring Member of Parliament. It goes without saying that I had wished to see you serve for longer and at a more senior level.”
Labour is now favourite to win back the bellwether seat, which has always been held by the party of government. Mensch has a majority of just 1,951 and it is the first time that the Conservative party has had to defend a seat in a by-election since entering government.
The vote is expected to take place on 15 November.
Labour candidate Andy Sawford said: “During the by-election we will focus on the two wasted years of Tory policies that have taken the country back into recession and left Corby suffering job losses in both the public and private sector.”
Elected as Louise Bagshawe in 2010, the novelist was parachuted into the marginal seat as one of the “A-list” – up-and-coming Conservative candidates who bought into Cameron’s modernising plan for the party.
After winning the seat from Labour’s Phil Hope she actively courted press attention, building up a dedicated online following before rising to prominence as part of the culture, media and sport select committee that cross-examined Rupert Murdoch over phone hacking allegations.