Rep. Jeff Flake is set to spend at least $1.4 million of his Senate campaign war chest on television advertising in his attempt to secure the Republican nomination.

Flake has found himself in a costly primary against self-funding real estate investor Wil Cardon. The ad buy is set to run from July 9 through the Aug. 28 primary.

Roll Call rates the general election as Leans Republican. Former Surgeon General Richard Carmona is the presumptive Democratic nominee.