Freedom's Watch is continuing to tie Kay Hagan to Jimmy Carter.

The Washington-based conservative advocacy group has sent a mailer to North Carolina voters linking Hagan's support for a windfall profit tax on oil companies to the former president's proposal.

"Why is Kay Hagan using Jimmy Carter's failed policies to fix the current energy crisis?" the mailer says.

Inside, it cites an editorial in Investor's Business Daily and a guest column in the Wall Street Journal by Republican Rep. John Shadegg to argue that Hagan would "make America dependent on foreign oil."

"Kay Hagan opposed offshore drilling to make America less reliant on foreign oil," it says.

Hagan initially opposed lifting a ban on offshore drilling, but later backed a failed bipartisan compromise that would have allowed some drilling and encouraged alternative energy.

Previously: Robocall targets Hagan on drilling.