Former Vice President Dick Cheney on Wednesday endorsed Secretary of State Trey Grayson in the state’s closely watched GOP Senate primary.

“I’m a lifelong conservative, and I can tell the real thing when I see it,” Cheney said in a written statement.

“The challenges posed by radical Islam and Al Qaeda are real and will be an on-going threat to our domestic security for years to come. We need Senators who truly understand this and who will work to strengthen our commitment to a strong national defense and to whom this is not just a political game,” Cheney said.

Recent polling has shown Grayson trailing Rand Paul, the son of Rep. Ron Paul (R-Texas), in the Republican primary.

Paul has sought to paint Grayson, a protégé of Senate Minority Leader Mitch McConnell (Ky.), as just another political insider while Grayson has attempted to make the case that Paul, an eye surgeon, is simply riding the political network built by his father. Earlier this week, Paul tapped that network to help raise more than $260,000 online in one day.