Both the Club for Growth and the Senate Conservatives Fund have already endorsed Sasse.
"Osborn is on a mission to repeal ObamaCare and replace it with common sense, patient-centered healthcare solutions," FreedomWorks PAC President Matt Kibbe said in a statement on Monday.
Kibbe also seemed to take a subtle jab at Sasse, a former assistant secretary of Health and Human Services under George W. Bush who has gone into extensive detail about his opposition to Obamacare.
"The Senate does not need more smart people with generally nice sounding ideas, it needs heroes. The time for giant voices and strong principles is now," Kibbe continued. "Shane Osborn has proven himself to be all these things and more. Nebraska and the country will be proud of the work Shane Osborn does in the Senate."