Lindsey Graham on Monday formally announced his bid for the White House.

South Carolina's senior senator announced his campaign in Central, the small town where he grew up.

Graham spent the majority of his 20 minute speech on foreign policy, telling his supporters that he wants “to become president to defeat the enemies that are trying to kill us. Not just penalize them, or criticize them, or contain them, but defeat them.”

“So get ready. I'm ready,” he said.

“I've got one simple message: I have more experience with our national security than any other candidate in this race, that includes you Hillary,” he said, a reference to former Secretary of State Hillary Rodham Clinton, considered the front-runner for the Democratic presidential nomination.

Graham promised to be a “voice for social conservative values without apology or animosity.”

The 59-year-old unmarried Graham, a vocal opponent of LGBT rights who has racked up an impressive anti-gay voting record while serving in Congress, has previously denied rumors he's gay.

In 2010, The New York Times posed the question to Graham.

“I know it's really gonna upset a lot of gay men – I'm sure hundreds of 'em are gonna be jumping off the Golden Gate bridge – but I ain't available. I ain't gay. Sorry,” he answered.

Graham is the ninth announced candidate for the Republican presidential nomination.

(Related: Lindsey Graham: US must “move forward” if Supreme court strikes gay marriage bans.)