The ad follows attacks from conservative groups on McConnell for his reluctance to sign onto a conservative-led push opposing the law that would, in effect, shut down the government if the law is not defunded.

Kentucky Opportunity Coalition (KOS), a nonprofit that has previously touted McConnell's work against ObamaCare in television ads, is launching a $325,000 statewide buy for another week's worth of commercials.

The ad notes the United Postal Service's decision to drop healthcare coverage for 15,000 employees, which the company said was caused by ObamaCare, as reasons McConnell "keeps on fighting to dismantle and defund ObamaCare before it hurts more Kentucky families."

It directs supporters to an online petition to "stand with Mitch against ObamaCare."

The group is advised by Scott Jennings, a former McConnell campaign manager who also advises Kentuckians for Strong Leadership, the super PAC supporting his bid.

The KOS ads give McConnell some cover for attacks from his right flank, and will allow him to continue his new focus on what he's calling Democrats' "war on coal," an attempt to hit his opponent on his left.

The Environmental Protection Agency is releasing regulations this week that seek to limit emissions from new power plants, an effort that will significantly squeeze the coal industry. It amounts, Republicans have said, to another volley in Obama's "war on coal."

And because the coal industry makes up a large part of Kentucky's economy, Republicans are looking to saddle McConnell's Democratic opponent, Alison Lundergan Grimes, with the baggage of Obama's climate policies.

She released a statement on Tuesday calling for Obama to "do the right thing" on coal, noting the significance it has for Kentucky's economy and pledging to defend the coal industry if she's elected to Congress.

McConnell and the state's Republican Party immediately latched onto the comments, with McConnell press secretary Allison Moore charging that her candidacy was "hatched by the very people waging war on Kentucky coal," namely Senate Leader Harry ReidHarry Mason ReidMcConnell not yet ready to change rules for Trump nominees The Hill's Morning Report — Sponsored by CVS Health — Trump’s love-hate relationship with the Senate Trump to press GOP on changing Senate rules MORE (D-Nev.), who has previously said that "coal makes us sick."

The campaign on Wednesday released a cinematic web video featuring clips of McConnell speaking on the significance of coal to Kentucky and pledging to defend the industry, laid over video of coal miners and the senator meeting with supporters.