City status is to be awarded as part of the Queen's Golden Jubilee celebrations and six regions are in the running for the Welsh bid - but the two firm favourites are Newport and Wrexham.
William Hill puts their odds at 2-1 each, while the next most likely to get city status is Newtown in Powys with odds of 100-30.
Wrexham CBC chief executive Derek Griffin said 56% of Welsh MPs, 75% of councils and 61% of Welsh Assembly members support the bid from north Wales.
Wrexham also boasts ex-footballer Ian Rush, comedian Ken Dodd, TV presenter Tim Vincent and the Duke of Westminster among its supporters.
Newport CBC countered widespread support for Wrexham's bid by claiming it has backing from four former secretaries of state - Ron Davies, John Redwood, Peter Walker and David Hunt.
Chairman of Newport's campaign for city status Ben Hoppe, who runs an engineering firm in the town, said: 'As secretary of state, they have each overseen Welsh affairs and I believe they can make an objective judgment about the competition. Their support demonstrates that Newport is important not only to south east Wales, but to Wales as a whole.'
City status is largely a matter of civic pride, but the improved profile of being a city can bring investment and jobs.
City status will be granted to one town in each of England, Northern Ireland, Scotland and Wales as part of the Queen's Golden Jubilee celebrations in June.