THE REPORT comes from Charlie Gasparino. The challenge to it is seen in another report that Karl Rove’s American Crossroads is investing a one-week buy of $16 million in Senate races, as well as Romney’s bid for the White House, which is $11 million of the buy, including the ad above.

From Gasparino:

The Romney campaign is experiencing what some officials believe could be the beginning of a mass exodus of big money donors diverting their cash away from the Republican presidential hopeful and toward Republican candidates for the House and Senate races more likely to win in November, the FOX Business Network has learned.

The buy by Rove is the biggest of the presidential cycle yet, according to Politico.