Paddy Power has given the Metro and Evening Standard publisher odds of 8/11 ahead of its rivals.
Transport for London kickstarted the tender earlier this week by putting a notice in the Office Journal of the European Union, stating that publishers have until April 21 to register their interest in the distribution rights for the proposed title.
According to Paddy Power, Associated Newspapers has emerged as the favourite, despite the Office of Fair Trading requiring it to forfeit its exclusivity rights agreement with TfL for the morning's Metro newspaper, because of its urgency to protect the Evening Standard's London monopoly.
Other bidders in the frame are Richard Desmond's Northern & Shell at 10/3, News International at 4/1 and Trinity Mirror at 8/1.
Desmond's wish to launch an evening title for London is no secret, given he complained to the OFT in May 2003 about Associated's exclusive deal with London Underground.
The success of Metro, which is now available in 15 UK cities, has proven beyond doubt the viability of a free London paper, with Guardian Media Group also among the contenders at 10/1.
TfL, which has already confirmed it has received a "significant amount of interest from publishers", now has less than 10 days to register interest from all of the interested parties.
The Beano is currently rank outsider on odds of 100/1.
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