The two billionaire candiates for governor in Illinois have spent tens of millions of dollars, and that's just in the primary.

CHICAGO (CBS) — The two billionaire candidates for governor in Illinois have spent tens of millions of dollars, and that’s just in the primary.

Gov. Bruce Rauner, who made his money in the investment business, has spent $57 million so far this election cycle.

JB Priztker, heir to the Hyatt hotel fortune, has so far spent $70 million,

It is shaping up to be the costliest gubernatorial campaign in U.S. history.

And what kind of return did the candidates get for spending that money?

Well, winning of course. (Rauner was locked in a close primary battle, while Priztker won by double digits.)

A breakdown of what they spent per vote:

Ranuer 361,283 votes or $157 a vote.

Priztker 573,636 votes of $122 a vote.

Both campaigns point out that total spending included building campaign infrastructure that will benefit the General Election effort.