It will save you a lot of money,I think.
A CPC (Cost per Click) campaign is a campaign were you pay a price every time someone clicks on your link, be it a banner, email, text link etc. A Cost-per-Lead (CPL) campaign is where you pay every time someone successfully fills out your lead form.
Usually there is a cookie on the “Thank You” page that fires every time some arrives there. This is to give the advertiser an idea of what kind of traffic and creative is working. At the end of the month, depending on your contract, you remove the duplicates, and tell the advertiser or agency how many leads you received. There is usually a scrub rate that is decided on before you start. These are the amount of leads you are allowed to discard due to internal duplicates, or other reasons.
If one of the conversion events of your campaign is that a lead is filled out, than why not turn you CPC campaign into a CPL campaign. Media folks will not be happy about me spilling the beans, but if they are not selling large portions of traffic, and you have money to spend, maybe you can convince them to turn your CPC campaign into a CPL campaign. » Read more: CPC Campaign VS CPL Campaign