Rick Santorum is on the verge of doing the "Full Grassley" for the second time.

That's a reference to Iowa Sen. Charles Grassley (R), who makes sure to visit each of the state's 99 counties every year. By his campaign's calculations, Santorum will reach the milestone next Tuesday, when he gets to Lyon County, in northwestern Iowa.

In the run-up to the 2012 Republican caucuses, Santorum did the "Full Grassley" in his underdog bid for president, traveling thousands of miles in a Dodge Ram 4x4 pickup driven by an aide. The Hawkeye State hegira built momentum for the former Pennsylvania senator, and he edged out Mitt Romney in the caucuses, the traditional first voting in the presidential nominating contest.

For what it's worth, Santorum is two months ahead of his pace four years ago. He did not hit his 99th county until November 2011.

Santorum plans a celebration in Island Park in Rock Rapids, Iowa Sept. 1, at 5:30 p.m. central time.

If anything, the going has been rougher for Santorum this time around. He has had some problems raising money, and he faces stiff competition for the evangelical Christian base that has dominated in recent Republican Iowa caucuses, from, among others, Texas Sen. Ted Cruz and former Arkansas Gov. Mike Huckabee.