By William Horobin

PARIS -- Former French President Nicolas Sarkozy was knocked out of the first round of a key primary, marking a significant upset in the race to become France's next president.

The results from 7,365 of the 10,228 polling stations across the country on Sunday showed Mr. Sarkozy winning only 21.7% vote after centering his campaign on pledges for hard-line security measures and a clampdown on immigration.

Mr. Sarkozy was hobbled by a late, surprise surge in support for his former prime minister, François Fillon, who ran in the conservative primary race on a platform of delivering a shock to the French economy with deep spending cuts and labor overhauls. Mr. Fillon won 43.7% of theearly votes, ahead of the 27.8% received by Bordeaux Mayor Alain Juppé, who recent polls showed had been the favorite to win the primary.

Mr. Fillon and Mr. Juppé will now advance to a runoff next Sunday. Mr. Sarkozy, who conceded defeat late Sunday, said he would throw his support behind Mr. Fillon.

The elimination of Mr. Sarkozy in the first round upends a conservative primary that is set to have sweeping consequences in France. Polls show the winner next Sunday would be best placed to win the presidential election in May against the far-right National Front's Marine Le Pen.

Until last week, polls had shown Mr. Sarkozy would easily reach the second round and go head-to-head with Mr. Juppé in a second-round race centered on questions of French identity and security in the aftermath of a string of terror attacks in France.

Write to William Horobin at William.Horobin@wsj.com

(END) Dow Jones Newswires

November 20, 2016 16:46 ET (21:46 GMT)

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