The 2016 presidential primary season continues to be predictably unpredictable, with outsiders leading polls and seasoned political veterans lagging behind. Every time Donald Trump says something offensive, it seems like it will finally be the statement that brings him down. But Trump continues to poll like a front-runner nationally, in Iowa and in New Hampshire.

But just because the last several months have mostly held steady doesn’t mean we should expect the candidates in the lead today to win caucuses and primaries. Most voters probably still haven’t made a final decision on whom they will support. Let’s review who led primary polls on Nov. 25, 2011, 2007 and 2003.