Democrats and Republicans in the Senate are proposing to toughen the nation's auto fuel efficiency rules, as the Bush administration seeks more money for research on environmentally friendly vehicles, according to a Wall Street Journal story by Jeffrey Ball. Two Democrats on the Senate Commerce Committee, John Kerry of Massachusetts and Ernest Hollings of South Carolina, plan to introduce a bill Feb. 8 that would require the nation's auto fleet to achieve an average of 35 miles per gallon by 2013, according to a person familiar with the discussions. That is a big jump from the fuel economy of the current fleet, which stands at about 24 mpg, the lowest level in 20 years, primarily because of the popularity of gas guzzling sport utility vehicles, pickup trucks and minivans. In addition, a Republican on the committee, John McCain, introduced his own bill Feb. 7 to increase the mileage standards, according to Pia Pialorsi, an aide to the Arizona senator. Although it wasn't clear precisely how big an increase his bill called for, a central feature of his proposal is to let auto makers satisfy as much as 10 percent of the requirement by trading emission credits with other companies, including those outside the auto industry, Pialorsi said.