It's a reference to the discharge petition introduced by House Minority Leader Nancy Pelosi (D-Calif.) last week to extend the Bush-era tax levels for the middle class but allow rates to rise for the wealthy. The petition will need 218 signatures to get to the House floor for a vote, and Democrats will be unable to achieve that majority without help from a few dozen Republicans.

The call goes on to charge that the targeted lawmaker is "holding the middle class hostage to get more reckless, budget-busting tax cuts for millionaires."

It directs the listener to go to GOPHostageTakers.com, a site launched by the DCCC last week that includes a petition for visitors to sign to "to tell Speaker BoehnerJohn Andrew BoehnerDems face hard choice for State of the Union response Even some conservatives seem open to return to earmarks Overnight Finance: Trump, lawmakers take key step to immigration deal | Trump urges Congress to bring back earmarks | Tax law poised to create windfall for states | Trump to attend Davos | Dimon walks back bitcoin criticism MORE and House Republicans to allow a vote on middle class tax cuts," and lists 40 House Republicans that it says are taking the middle class "hostage."

When launched last Wednesday, the site set a goal of 250,000 signatures on the petition; the DCCC says it has already received more than 400,000 signatures, and the site now lists a goal of 500,000. 

The robocalls, which are only going to the districts of 35 of the 40 "hostage-takers," are a slight escalation of an effort launched last week by the DCCC to hammer Republicans on the tax issue, at a time when negotiations surrounding the fiscal cliff are heating up on Capitol Hill.

The committee also sent press releases to reporters in the districts of the 40 targeted Republicans highlighting the discharge petition. The effort is an indication Democrats believe the issue of tax cuts for the middle class will be a potent one going into the upcoming election cycle.

The targeted lawmakers are as follows:

CA-10 Jeff Denham

CA-25 Buck McKeon

CA-31 Gary Miller

CO-06 Mike Coffman

FL-02 Steve Southerland

FL-10 Dan Webster

FL-13 Bill Young

FL-27 Ileana Ros-Lehtinen

IA-03 Tom Latham

IA-04 Steve King

KS-02 Lynn Jenkins

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NV-03 Joe Heck

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NY-22 Richard Hanna

NY-23 Tom Reed

OH-06 Bill Johnson

OH-07 Bob Gibbs

OH-16 Jim Renacci

OK-04 Tom Cole

OR-02 Greg Walden

PA-07 Pat Meehan

PA-08 Mike Fitzpatrick

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