Introduction

U.S. Sen. Pat Roberts waves to the crowd as he rides on the back of a pickup in a August 2014 parade in Gardner, Kan. Roberts is facing tea party-backed challenger Milton Wolf in the primary election Tuesday, Aug. 5. Charlie Riedel/AP

Moneyed nonprofits and super PACs so often peddle political poison, sending sorties of negative advertisements straight at a preferred candidate’s opponent. The candidate’s own campaign, in turn, stays positive.

But the script is flipped in Kansas, where groups attempting to save the political career of Republican Sen. Pat Roberts have invested big money in warm fuzzies designed to repel a primary challenge from tea party-backed upstart Milton Wolf.

Together, three political committees — sponsored by the American Hospital Association, American College of Radiology Association and National Rifle Association — have collectively spent $337,000 on ads and other messaging that promote Roberts, a Center for Public Integrity review of federal filings through Monday indicates.

Meanwhile, these groups, which are each headquartered in or near Washington, D.C., haven’t spent a cent on messages that attack Wolf ahead of tonight’s primary vote.

Why? Success, perhaps. This positivity strategy mirrors one that worked perfectly for another embattled career politician — Sen. Thad Cochran, R-Miss., who edged tea party favorite Chris McDaniel in an otherwise nasty GOP primary runoff.

Super PACs and nonprofits backing Wolf, for their part, have been overwhelmingly nasty in their pitches to Kansans.

Of the $809,000 they’ve collectively spent, $588,000 of it — about 73 percent — has funded ads that expressly attack Roberts, federal records show.

Virginia-based Senate Conservatives Action, the super PAC arm of the Senate Conservatives Fund — a group founded by Heritage Foundation president and former U.S. Sen. Jim DeMint — accounts for about $499,000 worth of these negative ads, which paint Roberts as an out-of-touch back bencher. The Georgia-based Tea Party Patriots Citizens Fund accounts for the rest of the anti-Roberts ad spending.

The only negative ads to target Wolf are sponsored by the Roberts’ campaign itself.

They include a recent television spot that pans Wolf, a radiologist by trade, for posting X-rays of his patients on Facebook and facing an investigation by Kansas’ medical board. (The American College of Radiology has shunned Wolf in favor of Roberts, although that’s probably more a function of Roberts’ perch on the Senate’s Health, Education, Labor, and Pensions Committee.)

“Unfit. Not trusted. Not right for Kansas,” the ad’s narrator declares.

Another ad chides Wolf for missing votes.

Roberts’ own negative ad spending likely arises from his lack of air cover from super PACs and nonprofits: Outside groups supporting Roberts have spent about 41 cents for every dollar spent by groups supporting Wolf or bashing Roberts, federal records indicate.

But when the money the candidates themselves raised for their primary campaigns through mid-July is added to the money spent by supportive outside groups, the power of incumbency — and the cash that typically comes with it — is revealed.

Team Roberts controlled about $4.8 million, while Team Wolf controlled just $1.82 million.

Ben Wieder contributed to this report.