New York—U.S. online ad spending will reach $31.3 billion this year, up 20.2% over last year, according to a new report from eMarketer. U.S. advertisers will spend $14.4 billion on search ads this year, up 19.8% over last year, and they will spend $12.3 billion on display ads, up 24.5% over last year, according to the report. This year, online advertising will make up nearly 20% of total U.S. ad spending, eMarketer projected. By 2015, online advertising will account for 28% of total ad spending.