Story highlights Hillary Clinton's campaign is taking new steps to try and disqualify Bernie Sanders in the eyes of Democratic voters

Clinton took fresh aim at the Vermont senator as part of a new strategy before the New York primary on April 19

New York (CNN) Hillary Clinton's campaign is taking new steps to try and disqualify Bernie Sanders in the eyes of Democratic voters, hoping to extinguish the argument that he is an electable alternative for the party's presidential nomination.

As Sanders took a victory lap following a 14-point triumph in Wisconsin, Clinton took fresh aim at the Vermont senator as part of a three-part strategy before the New York primary on April 19: Disqualify him, defeat him, and unify the party later.

"Some of his ideas just won't work because the numbers don't add up," Clinton told a labor union audience Wednesday in Philadelphia. "In a number of important areas, he doesn't have a plan at all."

It's the latest chapter in Clinton's approach to Sanders. She's tried ignoring him, brushing him aside, gently dismissing his policies. The Clinton campaign has refrained from going nuclear on Sanders, aides say, in large part to keep at least some good will alive in hopes of unifying the party at the end of the primary fight.

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