Republican Sen. Lindsey Graham is a leading advocate of U.S. intervention in the Syrian civil war. Graham is up for re-election in 2014, and so far he is facing three challengers in the Republican primary, none of whom are thought at the moment to represent a serious threat to his election prospects. But those three challengers — Nancy Mace, best known as the first woman to graduate from The Citadel; Lee Bright, a Republican state lawmaker; and businessman and evangelical Richard Cash — are all lining up to oppose the U.S. intervention that Graham favors. I asked for their response to Graham's position, and here are their answers.

"I find no compelling national security reason to engage our military in Syria," wrote Mace via email:

I believe American troops should be fighting against al Qaeda, not alongside them.

Bolstering an opposition dominated by al Qaeda will hurt our national interests and only deteriorate the situation in the middle east. Senator Graham continues to support President Obama's failed foreign policy. And just yesterday said he would try and "sell" a broader engagement to the people of South Carolina.

I will stand with the people of South Carolina against Obama's failed leadership and against military action in Syria.

From Lee Bright:

John McCain and Lindsey Graham seem willing to go to the ends of the earth to help the Muslim Brotherhood but think it is a “bridge too far” to defund Obamacare. McCain and Graham claim to be able to tell the good guys from the bad guys in Syria and that dropping a few bombs will solve all our problems, but South Carolina needs a Senator who will fight to protect us from domestic threats to our liberty like Obamacare not run around the world auditioning for Secretary of State.

Finally, Richard Cash did not send a specific response but referred to an article on his website, written before President Obama sought congressional approval for Syrian action, in which he slammed Obama for "preparing to inject America into a civil war in which we do not have a vital national interest" with "no coherent military strategy." Later, Cash sent a note adding:

I am glad that President Obama is seeking congressional approval. However, my concerns over both the limited action initially announced and the regime change that Sen. Graham seeks remains unchanged. Neither President Obama nor Sen. Graham has made the case that going to war in Syria is in our vital national interest.