Senator Lindsey Graham is suspending his presidential campaign.

The South Carolina senator is expected to make his official announcement in a Monday email to supporters, CNN has reported, adding that Graham still wants his opinions heard regarding where his party is headed, particularly regarding the Middle East. 

“To those in the Republican Party who want to win [against ISIS], check my plan out. Hillary, if you get to be President, I'll help you where I can. I hope you're not. But if you are, I'll be there to help you win a war [against ISIS] we can't afford to lose," Graham said to CNN.

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Graham’s announcement came on the deadline for him to remove his name from the South Carolina primary ballot, Politico added in a related report, which was important if Graham wanted to avoid a potentially underwhelming performance in his own state’s contest.

Graham said that part of the reason for his low profile has been the debate structure of the crowded Republican field of nominees, CNN stated.

"My biggest problem is a lot of people like what I say, but not a lot of people hear it," he said to CNN. "I don't want to be the undercard voice. I cannot tell you how frustrating it has been to have spent all this time and effort preparing myself to be commander-in-chief and to be put at the 'kiddie table.'"

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"I'm not trying to hold out. I'm trying to make a difference. I think the best way for me to make a difference is to think about helping somebody else," he was quoted by CNN.