New York City Mayor Bill de Blasio's push for a $15 minimum wage has put him in the cross-hairs.

The Employment Policies Institute, a conservative think tank, is running a full-page attack ad in the New York Post on Tuesday with the headline: "What's bigger than Bill de Blasio's Ego? New York's youth unemployment crisis."

The ad argues that "economic research and real-life stories make clear that [a $15 minimum wage] would be devastating for less-skilled jobseekers around the country - including the 32% of young adults in New York City who want a job and can't get hired at the current minimum wage." The ad has a picture of a young black woman.

De Blasio's press office fired back with its own attack on Richard Berman, the executive director of the group that placed the ad. Berman has a public relations and lobbying firm which has worked for the restaurant industry. De Blasio spokesman Peter Kadushin said Berman has made millions doing that work.

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"Raising the minimum wage will help create opportunity, lift New Yorkers making just $8.75 an hour out of poverty, and move New York's economy forward," said Kadushin.

The Employment Policies Institute has argued against a minimum wage of any level, and has been particularly active arguing against increases in the minimum wage that have been approved by various states and cities.

The federal minimum wage is $7.25 and hour, while New York State's is $8.75 an hour, and due to rise to $9 next year. The Obama administration is proposing a national minimum wage of $10.10 an hour, while de Blasio is pushing for a New York rate nearly 50% higher than that.

Despite the claims in the ad, there is conflicting economic research on whether or not raising the minimum wage causes unemployment to rise.