Divorced father-of-four Mark Adams, 56, raped his victim while she slept on the floor of his camper van on August 10, 2017.
This is his second conviction for rape. He was jailed for seven years at Woolwich Crown Court in January.
Today at the High Court in Glasgow judge Lord Armstrong ordered Adams to serve his latest sentence after the seven years he is currently serving.
The court heard that Adams, who forced his victim to relive her ordeal in court, now accepts he raped her.
Lord Armstrong told Adams: “You took advantage of a vulnerable woman in a calculated and manipulative manner when she was alone and making her way through the streets of Edinburgh.
“You are 56. You have expressed remorse. I may say, however, that is more than justified. A victim impact statement makes it clear your actions have had a devastating and detrimental effect on her.
“The crime of which you have been again convicted, rape, is a grave crime against which all women should be protected. That being so, this court will not flinch from making it plain that such crimes will attract a significant prison sentence.
“It is important that those who might be disposed to commit crimes of sexual abuse against women, in the way that you did, understand that they are likely to receive significant custodial penalties once brought to justice.”
Adams’ latest rape victim, who cannot be named for legal reasons, had fallen asleep in his van only to wake up and find Adams having sex with her.
Businessman Adams was jailed in England in January for raping a 24-year-old woman as she slept at his house near Blackheath, south-east London in 2015 on the morning after the general election.
The former civil servant claimed during the trial he had consensual sex with the Edinburgh teenager after she returned from a night out.
But, defence QC Gary Allan said: “Mr Adams has reflected on the evidence and he now accepts that whatever his thoughts at the time, whatever his view of the event, he now accepts that what he did amounted to rape.”
Cambridge graduate Adams,worked for the government for six years during the 1990s, and served as a private secretary to both Blair and Major, was awarded an OBE in 1997.
Adams was also convicted of sexual assault in a Welsh court last year.
He offered a barmaid £300 to spend the night with him and told her: That’s a lot of money to you isn’t it.”
When she said “no” Adams increased his offer to £400.
After leaving the Civil Service, Adams set up a public affairs agency called Foresight Consulting in 2001. His company acted for clients including the Police Federation.
In recent years he acted as a lobbyist and held high profile roles including chairman of the London Chamber of Commerce and Industry and of the Professional Lobbying Company. He also advised the Apprentice winner Michelle Dewberry as she attempted to become an MP.
In the latest case, the court heard harrowing testimony from his victim who had spent the evening of August 9, 2017, at a Fringe show with a male friend.
She walked home alone home after leaving a nightclub in Edinburgh around 5.15am feeling quite drunk and encountered Adams in Regent Street. He helped her into his camper van which was parked in the street.
She said “He bent down and picked me up and took me towards his vehicle. I was quite drunk. I was struggling to get into the van. He got in behind me. There was a mattress there and I almost immediately fell asleep.”
The woman said that she woke up to find Adams raping her and added: “I was just shocked and really traumatised.”
Taxi driver James Campbell, 50, who saw the victim shortly after the rape told prosecutor Dorothy Bain QC: “ She was distraught. She was totally broken.”
Adams, who was placed on the sex offenders’ register, showed no emotion as he was led away to the cells.
Sign up to our newsletter: enter your email in the box at the top of this article to get daily updates straight to your inbox.