The 2014 midterm elections are now just 31 days away. But those 31 days are valuable to candidates and independent groups vying, or some say trying to buy, your vote. That is especially true in the race for US Senate between Kay Hagan and Thom Tillis.

The fight for North Carolina’s Senate seat has been national news and fundraising fodder for months.

So how much money have the candidates brought in?

Nearly $11 million between them to date.

With just over $8 million raised Kay Hagan has a huge lead in the fundraising totals. That’s not surprising. Incumbents almost always have an advantage when it comes to raising money.

As for Thom Tillis, he has just shy of $2.75 million. One reason he’s well behind is the not so short – short legislative session this year which hampered his ability to raise money.

Between the two they’ve already spent more than $6.5 million on political ads that have aired more than 13,000 times statewide.

And yet, what the candidates have spent amounts to small potatoes.

The non-profit Center for Public Integrity has started a new project called “Who’s Buying the Senate.” Using national data from Kantar Media, a group that tracks who’s buying TV ads and how much they pay to air them, the Center for Public Integrity has been able to track and plot political ad buys for all the 2014 US Senate campaigns. And the Hagan-Tillis race tops their list as the most expensive race to date.

North Carolina is a relatively cheap media market. Still, more than $34 million have been spent to run a dizzying amount of ads, "Over 64,000 political ads have aired in the North Carolina Senate race," says Michael Beckel with the Center for Public Integrity, "During the last week of September alone about 6,200 ads aired. That’s about three ads every five minutes in North Carolina." The numbers are so high Beckel wrote a recent story titled, in part, "Eyeballs Burn In North Carolina."

But the sheer volume of ads isn't the only thing that makes the Tillis-Hagan contest stand out to Beckel. "One of the very notable factors in North Carolina is that about two-thirds of the ads that have aired in the state have been sponsored by groups that are neither political parties or the candidates themselves."

They are PACS, SuperPACS and politically active non-profit groups. So who is spending the most for either Tillis or Hagan?

"On the Democratic side, the Senate Majority PAC is a SuperPAC that has emerged as a major force in North Carolina," says Beckel, "That group alone is responsible for one out of every six ads that has run in the North Carolina senate race." They've spent around $5.3 million in support of Kay Hagan’s re-election.

As for the Republicans, Beckel says the biggest spender is Americans for Prosperity, which ties back to the Koch brothers. "That group has aired about one in every nine ads in the North Carolina Senate race."

When you take all this, the tens of millions of dollars to run tens of thousands of ads, you come up with the smallest but most surprising number so far...$4.96. That’s how much is being spent to per eligible voter in North Carolina on this one race. And there’s still more than a month to go.

Tom will be live tweeting the second debate between Hagan and Tillis on Tuesday, October 7.

You can follow him @TomWFAE.