The Senate’s approval Tuesday of an increase in the minimum wage, while played out politically by the Democratic Party, gives the poorest working Americans a needed break and gives Congress a far better chance of properly reforming the nation’s welfare system.

Both houses of Congress have approved a 90-cent-an-hour increase in the minimum wage, with an increase from $4.25 an hour to $4.75 initially and to $5.15 after a year. Both the House and Senate bills also would provide tax-break packages for businesses. The bills should not be difficult to reconcile and the package should be signed by President Clinton.

The minimum wage no longer is just the concern of teen-agers at summer jobs. More and more adults depend on it for longer periods of time to feed their families, with about 40 percent of all minimum wage employees the sole wage earners in their households. Had it kept pace with inflation over the last two decades the wage now would stand at $6 an hour. Under the current rate, a minimum-wage employee working 40 hours a week, 50 weeks a year would earn $8,500 annually, which is $3,700 below the poverty line for a family of three. Under the $5.15 wage, that employee would earn $10,300 annually.

Much of the debate over the minimum-wage increase centered on whether raising the wage kills jobs. Both sides displayed ample studies supporting their positions, but a former vice chairman of the Federal Reserve may have had the last word. Alan S. Blinder, a professor of economics at Princeton University, wrote last spring in the New York Times, “Frankly, I don’t know whether a modest minimum-wage increase would decrease employment or not. If it does, the effect will likely be very small.”

For people trying to buy enough groceries to feed a family and still make a car payment, however, the difference will be significant. For a government determined to change the nation’s welfare system, the increase allows it to tell recipients that many will be able to earn enough to get by as they are gaining experience in the workforce. A higher wage offers greater incentive to work.

The increase is hardly a king’s ransom, but it is a positive sign that Congress is occasionally willing to do something about the family values it talks so much about.