Recent polls show Americans view the IRS scandal as the most serious of the ongoing controversies surrounding the Obama administration, and also find that ObamaCare remains unpopular. Obama has weak poll numbers in many of the Republican-leaning states the group is targeting.

"Does 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 stand with President Obama and believe more of Alaskans’ hard-earned tax dollars should be given to the IRS to implement ObamaCare?" the NRSC asks in its release targeting Alaska's Democratic senator. 

"Like President Obama, does Mark Begich trust that the IRS will properly utilize the additional taxpayer dollars, rather than spend it on lavish staff retreats?"

Besides Begich, the NRSC targets include: 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 (D-Ark.), Mary Landrieu (D-La.) and Kay HaganKay HaganLinking repatriation to job creation Former Sen. Kay Hagan in ICU after being rushed to hospital GOP senator floats retiring over gridlock MORE (D-N.C.) Reps. 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 (D-Iowa) and Gary Peters (D-Mich.) and businesswoman Michelle Nunn (D), who is expected to run in Georgia. 

All but Nunn were in Congress when ObamaCare passed and voted for the law.

The Democratic Senatorial Campaign Committee fired back.

"Republican candidates will be forced to explain why they side with big insurance companies who are fleecing patients, discriminating against people with preexisting conditions, and cutting coverage for families when a loved one gets sick," DSCC spokesman Matt Canter said. 

"Last cycle national Republicans spent an estimated $200 million on ads attacking Democrats over Obamacare and every single Democratic Senator won reelection. This is a failed strategy, but they are welcome to continue their losing ways."

—This post was updated at 11:05 a.m.