McCain Inks South Dakota's Giant Killer

Sen. John Thune (R-S.D.) is throwing his support behind Sen. John McCain's (R-Ariz.) presidential bid, according to Paul Kane's Capitol Briefing blog.

Thune's support is significant for McCain as the South Dakota senator is not only beloved within the social conservative movement but is also revered among establishment Republicans for defeating the top Senate Democrat, Tom Daschle (D-S.D.), in 2004.

Thune is just the latest high-profile social conservative to make his preference in campaign '08 known early. As Alan Cooperman and I wrote recently in The Post, many social conservative leaders and activists are opting to side with McCain or former Gov. Mitt Romney (Mass.), making the pragmatic assumption that those two best combine a chance to win with solid stances on the issues most important to this crucial voting bloc.