North Carolina Senate candidate Elaine Marshall (D) is calling on former Sen. Alan Simpson (R-Wyo.) to resign as co-chairman of President Obama's fiscal commission following his statement about Social Security.

"Alan Simpson's remarks were disrespectful to women and to Social Security recipients," Marshall said in a speech Thursday in Charlotte. "He should resign or the president should fire him."

Simpson apologized Thursday to Ashley Carson of the Older Women's League for sending her an e-mail earlier in the week that sharply criticized Social Security and compared it to "a milk cow with 310 million tits."

Several lawmakers have also called for him to resign, but the White House said he will remain in his post.

"The fact that he thinks this way shows that he can’t do his job with an open mind," said Marshall. "We should be doing everything in our power to strengthen and protect Social Security, not attacking the recipients who depend on it."

-- This post was updated at 4:05 p.m.