GREENVILLE, S.C. — Presidential hopeful Michele Bachmann on Tuesday called for a wall on the border with Mexico and suggested that billionaire Warren Buffett should write a big check to the government if he’s eager for higher taxes on the wealthy.

The Minnesota Republican began a three-day swing through this early GOP primary state fresh off winning a narrow straw poll victory last week in Iowa over Rep. Ron Paul, R-Texas.

Bachmann said lax enforcement of immigration laws was a threat to the nation’s security. She agreed with a town hall questioner at a Greenville stop that U.S. troops should be redeployed from South Korea to south Texas.

“How do you solve it? You build a barrier, a fence, a wall — whatever you want to call it. You build it,” Bachmann said. “As president of the United States, every mile, every yard, every foot, every inch will be covered on that southern border.”

The “problem is not our laws on immigration,” Bachmann said. “The problem has been in our unwillingness to enforce the laws that are on the books.” South Carolina legislators this year passed one of the nation’s toughest illegal immigration laws. It goes into effect in December.

Bachmann criticized President Barack Obama’s call for the wealthy to pay higher taxes and Buffett’s support of the idea.

“We do believe, unlike Warren Buffett, that taxes are high enough already,” she said. “I have a suggestion: Mr. Buffett, write a big check today.”

In a state where candidates are rarely heckled, Bachmann got an earful. A man in a black suit called out repeatedly: “Are you anti-gay marriage.” During an interview Sunday, Bachmann was asked about her faith, same-sex marriage and whether she would appoint someone who was openly gay.

Bachmann noted the heckler and the interview questions. “I am not ashamed to say that I believe in God. We were founded on religious liberty and we are going to stand on religious liberty,” Bachmann said. “And we believe in marriage between one man and one woman.”