PRESIDENT BUSH moved in the right direction yesterday when he proposed rules that would make it easier to sell cheap generic drugs. These copycat medicines are supposed to be allowed on the market once the patents on the brand-name products they mimic have expired. But the brand-name companies have deployed legal maneuvers to extend their patents beyond the intended expiration, frustrating the price-cutters. If Mr. Bush renders some of those maneuvers illegal, health plans and consumers will save billions of dollars. The president's new position is especially welcome considering that he had previously sided with drug industry lobbyists and against consumers.

This conversion is going to need monitoring, because it seems to have been made with an eye to the midterm elections. The rising cost of prescriptions is a big pocketbook issue for voters, and it has favored Democrats, who have used their control of the Senate to pass a pro-generics bill that the Republican-controlled House has blocked. Yesterday's presidential proposal was apparently designed to neutralize the Democrats' advantage. Because it is only a proposal -- and because it will not be made final until after a 60-day comment period -- there's a danger that an election-season announcement will be diluted once the voting is safely done.

Moreover, the president's proposal omits many of the useful reforms contained in the Senate legislation. The main point in common is that both suggest limiting brand-name companies' ability to stifle competition by alleging that generic drugs infringe on their patents, which gets them an automatic 30-month patent extension. But the president's limits are looser; he does less than the Senate to prevent drug companies from fending off competitors by listing frivolous patents, and he does not address patent-holders' outrageous habit of paying would-be generic rivals not to bring cheap drugs to market.

The patented-drug firms are tough lobbyists, which is why the Senate's good legislation has been buried in the House. During the comment period, they will no doubt argue that their ability to finance medical research will be compromised if their patent rights are diluted. But promotion of research needs to be balanced against the imperative to make the fruits of research affordable. By exploiting legal loopholes to extend patents beyond their extended limits, the pharmaceutical lobby has skewed this tradeoff.

Yesterday Mr. Bush seemed to be grasping for a better balance. He declared of the pharmaceutical lobby: "You deserve the fair rewards of your research and development; you do not have the right to keep generic drugs off the market for frivolous reasons." It is now up to the president to follow through on that statement -- to go beyond yesterday's proposal, and beyond Election Day.