After six years in the Oval Office, there are just four states President Obama has failed to visit. On Wednesday he will knock one of them off the list, when he journeys to Idaho to speak at Boise State University as part of his post-State of the Union tour.

Which are the three others? South Carolina, South Dakota and Utah, it turns out.

It's not a great surprise that the four states the president has not yet visited in office are strongly Republican -- in Utah, for example, the 2012 GOP nominee Mitt Romney got 73 percent of the vote compared to Obama's 25 percent.

But Obama hasn't bypassed these places altogether -- in 2008 he gave a stump speech in Boise State's basketball arena to roughly 14,000 people. Idaho delivered its delegates to Obama, giving him crucial support in his contest against Hillary Rodham Clinton.

And just because a state didn't shower the president with electoral votes doesn't mean it loses out on a presidential visit. Oklahoma voters have been so wary of Obama he lost 15 counties in the state's 2012 Democratic primary to little-known opponents, and he got just  33 percent to Romney's 67 percent that fall.

But President Obama traveled to a pipe yard in Ripley, Okla. in March 2012 to tout the importance of oil in his energy policy, and he returned in May 2013 to Oklahoma City to inspect damage done by a tornado there.

So cheer up, South Carolina, South Dakota and Utah. Your time will surely come before January 2017.