This is his statement. But a Senate source points out to me that the “critical provisions” he mentions were in the bill that he voted against less than two weeks ago.

NELSON STATEMENT ON COCHRAN AMENDMENT TO IRAQ SUPPLEMENTAL SPENDING BILL March 27, 2007 – Nebraska’s Senator Ben Nelson issued the following statement on the Cochran amendment to the Iraq supplemental spending bill:
“Last week, I supported the Iraq supplemental spending bill that was approved by the Appropriations Committee. I do not support setting a calendar date for withdrawal from Iraq. However, the legislation also laid out benchmarks and required regular briefings to Congress. Setting measurable goals is absolutely essential for our strategy in Iraq and I have been pushing for these ‘conditions for staying’ for more than two years.
“Today, an amendment will be offered that would remove provisions of the bill. While the intent may be to remove the non-binding withdrawal date, the amendment goes beyond that. It would also remove several other critical provisions, including language acknowledging that the situation in Iraq has become a civil war and calling for diplomatic and political engagement on the part of both the Iraq and American governments. Such steps are necessary for success in Iraq and I do not support taking them out of the supplemental bill. Therefore, I will vote against this amendment.
“We can’t win Iraq’s civil war – that will take Iraqi leadership. Congress must begin the process of making the Iraqi government accountable for Iraq. To do so, we must deal with both the funding and future role of our troops. If we do not do so, we will be failing the American people.”