Has a major party presidential candidate ever opposed Medicare?

Every election winner since Medicare passed has supported it in their campaigns (their true opinions and records in office vary, but I'm just talking about the campaigns).

Nixon supported Medicare:

http://www.criticalpast.com/video/65675057117_Rich...

Ford supported Medicare (though he wasn't elected):

http://www.presidency.ucsb.edu/ws/index.php?pid=62...

Carter and Reagan argued over who supported Medicare more:

http://www.larrydewitt.net/Essays/Reagan.htm

Bush Sr. supported Medicare in 1988 (In 1989 he signed the bill repealing the Medicare expansion he had supported the previous year. In 1992, he lost reelection.)

http://www.nytimes.com/1988/07/09/us/bush-denies-a...

Bill Clinton supported Medicare

http://www.youtube.com/watch?v=XoBFL6iwid4

George W. Bush supported Medicare in 2000 and 2004 (he proposed a Paul Ryan type plan in 2005 and the Democrats took the House in 2006.)

http://www.cbsnews.com/video/watch/?id=640582n

http://talkingpointsmemo.com/archives/2010/02/game...

And of course Obama supported Medicare in 2008 (Republicans ran with great success in 2010 largely on claiming Obama had cut Medicare.)

http://www.youtube.com/watch?v=1Xi45Mf-P70

Every prospective candidate in the GOP field except for Mit Romney has thrown their support toward Ryan's plan to end Medicare. Have any major party candidates taken a position like that during a campaign before? Obviously if they did, they lost, but I'm curious if anyone ever even tried it in a Presidential race.