The committee is asking 12 Democrats — most of whom are up for reelection or running for Senate in 2014 — why they haven't made more noise about the IRS's admission it targeted conservative groups for additional scrutiny.

“Senate Democrats — who pressured the IRS to target conservative groups — have an obligation to defend the citizens and organizations that were bullied by their own federal government,” NRSC Communications Director Brad Dayspring said in a release.

Dick DurbinRichard (Dick) Joseph DurbinQuestions loom over Franken ethics probe GOP defends Trump judicial nominee with no trial experience Democrats scramble to contain Franken fallout  MORE is a United States Senator, and that requires action not just hollow press releases — but he continues to hide behind them" reads one release targeting Durbin (D-Ill.)

The Republican committee includes four questions it wants Democrats to answer, including whether the targeted lawmaker will return campaign contributions from the IRS union, whether they believe Obama should apologize to groups that were targeted and whether they'd like an independent counsel to investigate the misconduct.

There has not yet been a concerted push from Republicans in Congress to appoint a special counsel to investigate the issue but Senate Minority Leader Mitch McConnellAddison (Mitch) Mitchell McConnellAlabama election has GOP racing against the clock McConnell PAC demands Moore return its money Klobuchar taking over Franken's sexual assault bill MORE (R-Ky.) has indicated he's open to the idea.

Similar releases target 11 other Democrats. They include Sens. Mark WarnerMark Robert WarnerTech beefs up lobbying amid Russia scrutiny Overnight Tech: Senate Dems want FCC chief recused from Sinclair merger | Tech rallies on Capitol Hill for DACA | Facebook beefs up lobbying ranks Facebook adds two lobbyists amid Russia probe MORE (Va.), Mark BegichMark Peter BegichPerez creates advisory team for DNC transition The future of the Arctic 2016’s battle for the Senate: A shifting map MORE (Alaska), Mary LandrieuMary LandrieuYou want to recall John McCain? Good luck, it will be impossible CNN producer on new O'Keefe video: Voters are 'stupid,' Trump is 'crazy' CNN's Van Jones: O'Keefe Russia 'nothingburger' video 'a hoax' MORE (La.), Mark PryorMark PryorMedicaid rollback looms for GOP senators in 2020 Cotton pitches anti-Democrat message to SC delegation Ex-Sen. Kay Hagan joins lobby firm MORE (Ark.), Kay HaganKay HaganPolitics is purple in North Carolina Democrats can win North Carolina just like Jimmy Carter did in 1976 North Carolina will be a big battleground state in 2020 MORE (N.C.), Jeanne ShaheenCynthia (Jeanne) Jeanne ShaheenQuestions loom over Franken ethics probe State Dept. spokeswoman acknowledges 'morale issue' Democrats scramble to contain Franken fallout  MORE (N.H.), Al FrankenAlan (Al) Stuart FrankenReport: Conyers settled wrongful dismissal complaint over 'sexual advances' Arianna Huffington denies Franken behaved inappropriately in response to new photos Right way and wrong way MORE (Minn.) and Mark UdallMark UdallDemocratic primary could upend bid for Colorado seat Picking 2018 candidates pits McConnell vs. GOP groups Gorsuch's critics, running out of arguments, falsely scream 'sexist' MORE (Colo.) and Dick Durbin (Ill.) are all heading into reelection; Charles SchumerCharles (Chuck) Ellis SchumerJuan Williams: The politics of impeachment Texas Republicans slam White House over disaster relief request Dem rep: Trump disaster aid request is 'how you let America down again' MORE (N.Y.) will be up in 2016.

Also included in the attack are Reps. Gary Peters (Mich.) and Bruce BraleyBruce BraleyOPINION | Tax reform, not Trump-McConnell feuds, will make 2018 a win for GOP Ten years later, House Dems reunite and look forward Trump: Ernst wanted 'more seasoning' before entertaining VP offer MORE (Iowa), who have both announced they'll seek seats coming open because of retirements.

Schumer, Shaheen, Udall and Franken joined three other Democratic senators on a letter urging the IRS to do more to prevent political spending from tax-exempt nonprofits.

Democrats have fired back by pointing out that Senate Minority Leader Mitch McConnell (R-Ky.) has previously called for tougher IRS scrutiny for groups on both the left and right.

"No rational human being including Mitch McConnell thinks that Karl Rove and the Koch Brothers are operating social welfare organizations that deserve tax exempt status," said Democratic Senatorial Campaign Committee spokesman Justin Barasky. 

"However, Democratic Senators have been outspoken in their condemnation of what took place at the IRS."

In a Wednesday email to The Hill, DSCC Deputy Executive Director Matt Canter suggested Republicans were "overreaching" by continuing to hammer Democrats who have already all already condemned the IRS's actions.

Canter also noted warnings from other Republicans for lawmakers to avoid overreacting in their focus on the series of scandals that has plagued the Obama Administration over the past two weeks. He compared the potential fallout for Republicans to the 1998 election cycle.

After winning majorities in both the House and the Senate in 1994 and moving to enact more conservative policies, Republicans lost seats in 1998.

"Republican foolishness like this has many objective analysts wondering if 2014 could look like a repeat of the 1998 midterms," he said.

"Compared to today's GOP, a more moderate breed of Republican came into power in 1994, stormed the Bastille with unpopular policies that led to electoral defeats in the presidential year. They returned recognizing that their policies were disastrous for them politically, and promised to focus on jamming a President."

--This post was updated at 12:38 p.m. to reflect further comment from the DSCC.