A Senate Republican introduced legislation today aimed at preventing Democrats from adding cap and trade to a House and Senate energy conference, a move anticipated by some Republicans if the Senate fails to pass a climate bill under normal procedures. The amendment from Sen. Mike Johanns (R-Neb.) would require the support of two-thirds of the Senate, or 67 votes, to include cap-and-trade climate legislation in a House-Senate conference report if the Senate has not already debated and approved it with the normal 60-vote threshold.