HARTFORD, Conn. (CBSNewYork/AP) — Larry Kudlow, a financial and economics writer and broadcaster, said Tuesday that he is moving closer to announcing a challenge to U.S. Sen. Richard Blumenthal (D-Conn.) next year after the first-term lawmaker announced his support for the Iran nuclear deal.

Kudlow, a conservative commentator who served in the Reagan administration, said three weeks ago he’d challenge Blumenthal if the Democrat voted for the Iran deal. He said Tuesday he would not immediately announce his decision, but said he’s “moving closer to a run.”

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He said Blumenthal is taking a “party line” vote and called it a disservice and a blunder.

Blumenthal said Tuesday his decision was based on “conscience and conviction” and he expects to be held accountable for all his Senate votes.

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Blumenthal said the agreement “using diplomacy, not military force, is the best path now available to prevent a nuclear-armed Iran.”

“A simple blunt fact is that our formal negotiation partners and allies have signaled clearly they are not coming back to the table, a point confirmed to me in my personal conversations and meetings,” Blumenthal told WCBS 880. “So there is really no better deal available now, and the present sanctions are soon going to be unenforceable, producing an economic windfall for Iran whether or not accept this agreement.”

August Wolf, a former Olympics shot putter, is already seeking the GOP nomination to challenge Blumenthal.

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