The House hasn't voted yet on whether to reject a short-term payroll tax cut extension that the Senate passed overwhelmingly on Saturday, but House Democrats are already crying foul.

The Democratic Congressional Campaign Committee (DCCC) is targeting House Republicans in 20 districts with automated phone calls, online ads and a new website, and demanding they support an extension to a tax cut aimed at the middle class.

Dem pundit James Carville has recorded some of the individualized calls, and DCCC Chairman Steve Israel (N.Y.) has attached his name to statements going out in more than 70 Republican-held districts — the first time this year that Israel has attacked individual members, according to the committee.

House Speaker John BoehnerJohn Andrew BoehnerDemocrats eager to fill power vacuum after Pelosi exit Stopping the next insurrection Biden, lawmakers mourn Harry Reid MORE (R-Ohio) has already signaled his opposition to the Senate compromise measure and predicted the House will vote it down Monday night, citing GOP reluctance to punt on the tax cuts by approving only a two-month extension. Although President Obama and congressional leaders sought a full-year extension, disagreement over how to pay for it led the Senate to approve a stopgap extension with bipartisan support.

“Something remarkable happened this weekend. Democrats and Republicans in the Senate worked together to stop a $1,000 payroll tax hike on 160 million middle class families," Carville, a prominent Democratic strategist and former Clinton aide, says in a recorded call going out to a district in Ohio. “Sounds too good to be true? It is, if Rep. Bob Gibbs doesn’t do the right thing and support it."

Other Republicans whose constituents will be receiving the calls include Reps. Joe Barton (Texas), Renee Ellmers (N.C.), Michael Grimm (N.Y.) and Tim Murphy (Pa.).

Israel will push a similar theme in email blasts to reporters in districts held by Republicans, alleging that GOP partisanship will hit struggling Americans in the wallet.

“Thirty-nine Republicans in the Senate voted for a middle class tax cut compromise, but Rep. [Jeff] Denham is ready to scuttle it and sock the middle class with a tax hike on Jan. 1. That’s not right," Israel says in a statement knocking the California Republican.

Republicans, meanwhile, are also wasting no time in seeking political advantage from the ongoing kerfuffle. Coming to their aid is a vow by Democratic leadership in the Senate not to return to Washington for additional votes to approve a House-backed version of the extension.

House Republicans are pouncing on that pledge as evidence that Democrats in both chambers are more concerned about their vacation than about ensuring a full extension of the tax cut — even though 39 Republican senators voted for the deal that Senate leaders from both parties struck with the White House.

The National Republican Congressional Committee is training its sights on dozens House Democrats, denouncing them not only for their anticipated vote against BoehnerJohn Andrew BoehnerDemocrats eager to fill power vacuum after Pelosi exit Stopping the next insurrection Biden, lawmakers mourn Harry Reid MORE's two-month extension but also for voting earlier against a House GOP version of the bill that included a full-year extension that also froze pay for federal workers.

"While Shuler vacations, North Carolina families will face the uncertainty of higher taxes in 2012 when the clock strikes midnight on New Year’s Eve," NRCC spokeswoman Andrea Bozek said in a statement targeting Rep. Heath Shuler (D-N.C.). "Why won’t Shuler put North Carolina families before his own self-interests?”