Vaughan, 33, resigned as England captain last month and then stood down from the final match of the South Africa series, which England won under new skipper Kevin Pietersen.
However, the Yorkshire batsman insisted he wanted to continue his England career. However, runs have been hard to come by for Vaughan.
His last fifty, for Yorkshire, was followed by scores of two, nought, 21, nought and 17 against South Africa.
A break from cricket did not lead to an upturn in his fortunes when he came back, with Vaughan managing just 10, nought and 19 in his next three innings for his county.
"The central contract is a huge bonus, if I am honest I think I am lucky. I haven't got the runs properly to justify that position," Vaughan told BBC Radio Five's Sportsweek programme on Sunday.
"I think it has shown a hell of a lot of faith.
"But over the last year and a half I have had some excellent innings. I have had some good times with the bat not too long ago.
"I think they have just repaid the fact that if I get back into form I think I can still play a huge part in the England cricket team."
Next year, England host Australia for an Ashes series. Vaughan, who led England to glory in 2005 on home soil before missing the last Ashes series, in Australia in 2006/07 when England were thrashed 5-0, through injury would love to have one more go at the 'old enemy'.
But first he must win his England place back and, with the selectors due to name their squad on September 29, time is running out for Vaughan to secure a spot for the two-Test tour of India, with Yorkshire having just two more first-class matches before the English season ends later this month.
"I need some runs," said Vaughan. "That's not something I am desperate to do, I'm just going to try to let it happen.
"Sometimes if you are too desperate to do something it goes further and further away from you."
He added: "I haven't played that well in the last couple of months but form is temporary, the element of class will also be there.
"I have just got to get back to that form. The fitness is as good as it has been for a long while.
"I want to play for England - that is my goal over the next 12 months, to make sure I get that one last crack.
"I know it will be the last crack because you don't get a second crack when you get to the age of 33, 34.
"It will be one last chance to hopefully go out there and try to score some Test hundreds."
In 82 Tests, Vaughan has scored 5,719 runs, including 18 hundreds at an average of just over 41.