"Without Tom pushing it, I don't think we would have had Romneycare," Romney said of Stemberg, who died earlier in the day.
Romney added, "Without Romneycare, I don't think we would have Obamacare. So, without Tom a lot of people wouldn't have health insurance."
Mitt Romney general - updated 5/19/2015
Mitt Romney has made a surprising comment about Obamacare
Mitt Romney and Evander Holyfield fight in a charity boxing event on May 15, 2015 in Salt Lake City, Utah. The event was held to raise money for 'Charity Vision' a charity that aims to restore sight to the blind and visually impaired. (Photo by George Frey/Getty Images)
Mitt Romney Visits 'The Tonight Show Starring Jimmy Fallon' at Rockefeller Center on March 25, 2015 in New York City. (Photo by Theo Wargo/NBC/Getty Images for 'The Tonight Show Starring Jimmy Fallon')
Mitt Romney is greeted by fellow Republicans at a dinner during the Republican National Committee's Annual Winter Meeting aboard the USS Midway on January 16, 2015 in San Diego, California. Romney is contemplating a possible 2016 presidential run. (Photo by Sandy Huffaker/Getty Images)
Former Massachusetts Gov. Mitt Romney addresses the crowd during a rally for Republican Senate candidate Dan Sullivan at a PenAir airplane hangar on November 3, 2014 in Anchorage, Alaska. The U.S. Senate race in Alaska between incumbent Democratic Sen. Mark Begich and Republican candidate Dan Sullivan continues to be closely contested. (Photo by David Ryder/Getty Images)
Former Massachusetts Gov. and GOP presidential candidate Mitt Romney makes his way through supporters of Iowa Republican State Senator and U.S. Senate candidate Joni Ernst on October 11, 2014 in Cedar Rapids, Iowa. Ernst and Romney met with around 300 supporters at the event, one of many in the final weeks of Ernst's campaign for a U.S. Senate seat. U.S. Representative Bruce Braley (D-IA) and Ernst are virtually tied in polling to replace the seat occupied by retiring U.S. Senator Tom Harkin (D-IA). (Photo by David Greedy/Getty Images)
Governor Charlie Baker was sworn in as the governor of Massachusetts at a ceremony inside the House Chamber at the State House on January 8, 2015. Mitt Romney greets Chris Christie after Gov. Baker's swearing in. (Photo by John Tlumacki/The Boston Globe via Getty Images)
Mitt Romney attends the New York Jets vs. Miami Dolphins game at MetLife Stadium on December 1, 2014 in East Rutherford, New Jersey. (Photo by Al Pereira/WireImage)
Former Massachusetts Gov. Mitt Romney walks to the stage during a rally for Republican Senate candidate Dan Sullivan at a PenAir airplane hangar on November 3, 2014 in Anchorage, Alaska. The U.S. Senate race in Alaska between incumbent Democratic Sen. Mark Begich and Republican candidate Dan Sullivan continues to be closely contested. (Photo by David Ryder/Getty Images)
Former Republican presidential candidate and former Massachusetts Governor Mitt Romney, delivers remarks during a 'CoMITT to the Comeback' rally for Michigan republican candidates October 2, 2014 in Livonia, Michigan. Among the Michigan candidates in attendance were U.S. Senate Candidate Terri Lynn Land, Lt. Gov. Brian Calley, Attorney General Bill Schuette, and Secretary of State Ruth Johnson. (Photo by Bill Pugliano/Getty Images)
Ann Romney and former Governor of Massachusetts Mitt Romney attend the 3rd Annual NFL Honors at Radio City Music Hall on February 1, 2014 in New York City. (Photo by Slaven Vlasic/Getty Images)
LAS VEGAS, NV - DECEMBER 08: Former Republican presidential candiate and Massachusetts Gov. Mitt Romney sits ringside fro the Patrick Hyland and Javier Fortuna WBA interim featherweight title fight at the MGM Grand Garden Arena on December 8, 2012 in Las Vegas, Nevada. (Photo by Al Bello/Getty Images)
Republican presidential candidate Mitt Romney arrives on stage on election night November 7, 2012 in Boston, Massachusetts, moments before conceding defeat to US President Barack Obama in the 2012 US presidential election. AFP PHOTO/EMMANUEL DUNAND (Photo credit should read EMMANUEL DUNAND/AFP/Getty Images)
Discover More Like This
BACK TO SLIDE
Political observers widely found that to be an eyebrow-raising comment. During the 2012 election, Romney criticized President Barack Obama's signature healthcare bill, which is one of the most reviled pieces of legislation among conservative activists.
But as Romney's critics pointed out at the time, he pushed for a relatively similar healthcare overhaul in his state, including the controversial insurance mandate.