"I am disappointed," DeMint said Wednesday on CNN's "American Morning." "We have to stop spending more than we're bringing in."
Six GOP presidential candidates have signed the pledge so far. The Minnesota congresswoman argues it doesn't go far enough to bring down the deficit.
DeMint, a South Carolina kingmaker and early supporter of the tea party movement, has said a commitment to the pledge is necessary in order to win his support, which could prove valuable in the early voting state of South Carolina and within his larger conservative following.
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