In it, but not of it. TPM DC

Obamacare Foes Have Outspent Supporters 5:1 On TV Ads

AP Photo / Molly Riley

"The biggest advertisers in opposition to the ACA since its enactment have been Republican outside groups," the Kantar analysis concluded. "The biggest advertiser in support of the law has been the US Department of Health and Human Services in a nonpolitical (judging from the buy) education campaign."

Meanwhile, Kantar found, "Democratic candidates for office -- including President Obama himself -- have spent comparably little on campaign and issue advertising about the law."

The lopsided nature of Obamacare-related TV advertising may offer some context to the law's unpopularity in public opinion polls. A CNN survey last week found that 54 percent of Americans have an unfavorable opinion of the law, compared to 43 percent who view it favorably.

The gap illustrates the challenges facing the Obama administration and other proponents of the law as they fend off Republican efforts to sabotage the health care law's implementation. Democrats say they're increasingly dedicated to making sure the roll out of the law's major provisions next year goes well.