WASHINGTON, D.C. (KDAL) - Senator Al Franken is urging the Commodity Futures Trading Commission to fulfill its duty and limit excessive oil speculation to prevent oil producers from artificially inflating fuel prices.  Franken is also calling on the Office of Management and Budget to allow an increased use of domestic biodiesel to further reduce the nation's dependence on foreign oil.  He says with gas prices nearing a statewide average of 3.59 a gallon and more increases expected as the weather warms up, action needs to be taken to stem the rising costs of gasoline and keep them from spiraling out of control.