The singer-songwriter will perform the ballad 'Undo' on Saturday evening in Copenhagen, Denmark and currently has odds of 11/4 to take home the prize, according to bookmaker William Hill.
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Austria's Conchita Wurst is close behind in second at 3/1, while the Netherlands' country music duo The Common Linnets share the same odds.
The UK's entry Molly, looking to be the nation's winner for the first time in 17 years, isn't too far behind, at 5th with 9/1.
At the other end of the scale, San Marino and Belarus are the biggest outsiders at 250/1. Germany, Slovenia and Montenegro are also above the 200/1 mark.
William Hill's Eurovision 2014 odds in full:
United Kingdom 9/1