That’s one of the biggest clichés in politics. It’s also true in one-point races. Welcome to Iowa, Kansas and North Carolina.

According to the latest round of Fox News Senate battleground polls, none of the front-runners in those states hits the 50 percent mark. That means these races will be decided by late-deciding voters — and campaigns competing furiously to get their voters to the polls.

One thing that is baked into the cake: President Obama is unpopular in these states. That will motivate Republican voters, yet there’s more to these races — and with four days until Election Day, a lot could happen.

Let’s start in Kansas, which has the most volatile Senate race.