A bipartisan bill to allow supermarkets and big-box stores to sell gasoline and prescription drugs at discount prices is on life-support.

The measure now heads to the Senate, where it may be suffer a defeat as rural lawmakers team with independents and small-time petroleum distributors to kill the bill.

Opponents fear that the bill would help giant retailers such as King Soopers, Safeway and Wal-Mart seize the market.

"The independents are obviously targeting senators and claiming (that) giving consumers discounts on gasoline will put them out of business," said co-sponsor of the bill Sen. Steve Johnson, R-Fort Collins. "I think we, as lawmakers, need to let competition work."

House Bill 1208 was introduced after a small, rural gas station, citing a 70-year-old predatory pricing law, last year won a $1.4 million court judgment against King Soopers for selling gas 40 cents below cost for more than a year and passing on the discount to customers who bought groceries.

"The only point of selling gasoline at prices so low is to drive out competition," said Eric Balenseifen, president of Denver-based Rex Oil Company, a small distributor of petroleum products.

HB 1208 would allow gas and prescription drugs to be sold at lower costs. It would exempt King Soopers and other big- box stores from the Colorado Unfair Practices Act, which prohibits retailers from selling gas below costs.