Clinton Tweet: World Is Round, Vaccines Work Another potential 2016 candidate weighs in after Christie comments By Matt Cantor, Newser User Posted Feb 3, 2015 11:32 AM CST 205 comments Comments Hillary Rodham Clinton speaks to a crowd in Saskatoon, Saskatchewan, on Wednesday, Jan. 21, 2015. (AP Photo/The Canadian Press, Liam Richards) (Newser) – After Chris Christie's call for "choice" in vaccination landed him in trouble, Hillary Clinton is making no bones about her own position. "The science is clear: The earth is round, the sky is blue, and #vaccineswork. Let's protect all our kids. #GrandmothersKnowBest," she posted on Twitter last night. Her comments also come after a third potential 2016 candidate, Rand Paul, suggested that vaccines be "voluntary," USA Today reports. While Clinton's views seem clear, some commenters point to a Washington Free Beacon report noting that in 2008, neither she nor Barack Obama seemed so sure about vaccines.