The Trainspotting star is just 12/1 in the betting to replace Jodie Whittaker, having played a leading role in the latest series of Line Of Duty, while Kris Marshall and Michaela Coel continue to head the betting at 6/1 apiece.
The current Doctor Jodie Whittaker is set to quit the show after three years in the role.
The 38-year-old, who became the first female star to take on the famous character, will leave the show at the end of the next series, when she will regenerate into the 14th Time Lord.
The actress told producers she plans to stick to the tradition of giving up the role of Doctor Who after three stints.
The star is said to be is keen to take on new roles, with producers preparing for the next regeneration.
MacDonald is currently causing chaos as DCI Joanne Davidson in the BBC show alongside Martin Compston and Vicky McClure, but many would be delighted to see her take on the role as the famous Doctor.
Alex Apati of Ladbrokes said: “The race to replace Jodie Whittaker is more wide-open than it’s ever been and Line Of Duty fans will be pleased to see Kelly Macdonald’s odds have tumbled substantially over the past few weeks.”
Kelly Macdonald admitted last week that she gets as confused as viewers by all the quirky abbreviations on the hit cop show.
Kelly says the terminology confused her so much that she was nervous, and didn’t immediately accept the part she was offered on the series.
She said: “I did have to think about it. The shock, really, was when I read the first episode. Suddenly it was just, ‘Oh, there’s a massive long stream of dialogue about stuff I’ve never heard of’.”
“I did have to get over that obstacle in my mind, because I knew that was going to be quite challenging.”
Kelly who has been living Stateside since 2010 while starring in TV drama Boardwalk Empire had a lot to catch up on but admits others in the cast and crew helped her out.
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She said: “There would be certain acronyms we would discuss in rehearsals. And hair and make-up had a list of what everything stood for.
“I’m not brilliant at it still, but I get by.”
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