DDB saw its odds improve as the Omnicom-owned agency attracted further interest from punters. There are two other agencies also in the running -- Bartle Bogle Hegarty and JWT on 7/1 and 10/1 respectively.
The news followed M&C Saatchi's first-half results yesterday as it said its outlook depended on the outcome of the pitch. Pre-tax profits were up 1.7% to £4.1m.
M&C, which has held the BA account for more than 20 years, remains odds-on favourite at 4/5 to hold on to the account.
DDB has seen its odds shortened dramatically in Paddy Power's betting market after a week of media speculation and shrewd bets.
DDB was a 14/1 relative outsider when betting opened in July before being cut to 5/1 on announcement of the pitch shortlist. However, since then DDB has been the fashionable bet coming in dramatically to 11/8 in the last week.
Paddy Power, spokesman for the bookie, said: "With the advertising account still under review the betting and media rumours suggest that DDB are giving the Saatchi boys a real run for their money. Its starting to look like a two-horse race to land the BA account."
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