Contrary to popular belief, it was the Wall Street Journal that originally claimed Paul Ryan's "Path to Poverty" would effectively kill Medicare.
Fact-checking organization Politifact however chose to assign that accusation to the Democratic Party after Democratic politicians began repeating the Wall Street Journal's analysis. Politifact then chose "Republicans voted to kill Medicare" as their Lie of the Year.
The Wall Street Journal opined on Politifact's decision yesterday and agreed with the critics that Politifact is wrong.
The outrage over PolitiFact’s decision to declare the claim that Rep. Paul Ryan’s (R-WI) budget would end Medicare as the lie of 2011 has spread to the conservative Wall Street Journal, which explains in a Best-of-the Web feature today, the charge is “an assertion that combines elements of fact (Republicans did vote), interpretation (“end Medicare” means different things to different people) and prediction (about how the Ryan plan, if enacted, would work out in practice) That is to say, it is a statement of opinion.” The paper adds, “by practicing a style of journalism that centers on baselessly impugning the motives of others, it has managed to earn distrust across the political spectrum.”
I don't necessarily agree that it was a statement of opinion, however it seems clear that Politifact's rationale is flawed.