Running for President ain't cheap. Campaign spending runs the gamut from salary payments, to travel costs, and to consultant fees.

And then there's the biggest cost: advertising. A decent-sized television ad buy can cost anywhere from six to seven figures, depending on the state.

All of this money is spent, of course, in the hopes of turning out the most votes, which begs the question- how much are campaigns spending per vote on these ad buys?

ABC News crunched the numbers using a combination of our vote totals, and total spending numbers from the Associated Press.

Romney campaign: $4.37 per vote received so far.

Romney and the pro-Romney Super PAC "Restore Our Future:" $12.40 per vote received so far.

Santorum campaign: $1.65 per vote received so far.

Santorum and the pro-Santorum Super PAC "The Red, White and Blue Fund": $3.01 per vote received so far.

Gingrich campaign: $1.38 per vote received so far.

Gingrich and the pro-Gingrich Super PAC "Winning Our Future": $4.76 per vote received so far.

Paul campaign: $6.15 per vote received so far.

Paul and the pro-Paul Super PAC "Endorse Liberty": $6.32 per vote received so far.