Republican Sam Brownback may be backing out of the presidential race. The Kansas senator, who calls gay marriage a "social experiment", says his campaign's relying on Iowa to decide his fate:

…Brownback said Wednesday he will drop out of the race for president if he finishes lower than fourth place in the Iowa caucuses.
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In response to a questioner who asked whether Brownback planned to end his bid if he places outside the top four contenders, Brownback said, "That is correct. I need to finish in that group to move on forward."

Recent polls show that only two percent of Iowans are voting for Brownback, so he'd might as well just quit now.