todd foreman talks us through the pipeline predicament as it stands now. >> reporter: the president is trying to score something of a hat trick with his approach to the pipeline by voicing his approval for the bottom part of it down here to the gulf of mexico. the reason republicans are attacking, however, is they're saying this is more of a local issue. the states and local municipalities can handle this part. what the president is needed for is the upper part, the part that goes across the international border with canada. that's why they're attacking. why do i call it a hat trick that he was trying to pull off here? first of all, he's trying to address the issue of energy independence. about half of the oil we use in our cars, gas, comes from imported oil, oil that comes from other countries somewhere. about a quarter of that comes from canada, our biggest supplier. the new pipeline by most estimates would bring about 700,000 additional barrels a day. that's not actually a huge amount compared to how much oil we use, but over ten years this number is expected to rise maybe as high a