More 'convinced than ever' Hillary will be president: WPP

Democrat presidential hopeful Hillary Clinton is the most likely winner of the presidential election, the chief executive of the world's biggest advertising company told CNBC on Friday.

WPP Chief Executive Martin Sorrell reiterated a recent comment in which he said he thought Clinton, who is currently looking the most likely nominee for the Democrats, will be the next president of the United States.

"I feel actually a little bit more confident (now)" Sorrell told CNBC Europe's "Squawk Box" on Friday.

"We'll see what happens, it's a very unpredictable campaign but I'm either equally certain or more certain that Hillary will be in the White House come November and next year but there have been a number of surprises so far -- every time they attack Trump he gets stronger in the polls."

"But (Republican presidential hopeful Donald) Trump has a long, long way to go and Florida is critical not just because of its size and importance but because that is the heartland for (rival Republican nominee Marco) Rubio," he said

Martin Sorrell, chief executive officer of WPP, pauses during a session on the opening day of the World Economic Forum in Davos, Jan. 22, 2014.
Chris Ratcliffe | Bloomberg | Getty Images
Martin Sorrell, chief executive officer of WPP, pauses during a session on the opening day of the World Economic Forum in Davos, Jan. 22, 2014.

WPP's CEO said the company had a couple of companies working on the election in various ways and that the it was doing a lot of technical, data-driven media buying.

Sorrell noted that Trump had not been a "great believer in advertising, he's been a much greater believer in word-of mouth" but that he was starting to spend some money on advertising for his presidential nomination campaign.

On Friday, WPP, which handles the advertising needs of brands such as Ford and Unilever, reported fourth-quarter like-for-like net sales growth of 4.9 percent, the strongest quarter of the year and giving it a full-year figure of growth 3.3 percent, broadly in line with forecasts.

Sorrell said that the company had seen a "very good year in difficult circumstances, currency headwinds in the second half in particular."

Western Europe continued to improve, the U.S. was "very strong" but business was "patchy" in Asia Pacific, Latin America, Africa, the Middle East and central and Eastern Europe, he said.

WPP expected similar net sales growth in 2016 with sporting and political events such as the Olympics, European football championships and presidential election in the U.S. expected to boost media rates.

He warned that the wider economic environment did not inspire much optimism. "The fact of the matter is that the world economy is slow growth, there's very little inflation and as a result there's very little pricing power and you know that people are very focused on cost...add to that geopolitical uncertainties and clients are quite cautious" he said.

- Reuters contributed reporting to this story.

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