It's poking up everywhere like daffodils through the melting snows of the Reagan revolution. Six months ago, it was still the L-word, the political philosophy that dared not speak its name. Careful believers called themselves ''progressives.'' Even brave ones dared no more than ''neo-liberal.'' Old liberalism - social-program liberalism - was discredited.

It still is, in the sense that no one believes in throwing big money and big Government at poverty anymore. But liberalism, chastened by its years in the cold, is making a sudden comeback. The aim's the same, to help disadvantaged people who need comfort, care or opportunity. What's different is that the means are no longer wishful or wasteful.

Millions of children are growing up miserably poor and the country must do more to support them, says Senator Daniel Patrick Moynihan of New York. But he calls for a new system that provides public assistance only when the parents agree to provide their fair share. The welfare recipients who need jobs most are least likely to get them, says Senator Edward Kennedy of Massachusetts. But his imaginative jobs proposal would shell out funds only to states that first demonstrate the ability to get people into jobs and thus save welfare money.

California has developed ''social contracts'' that promise welfare for work, and New York contemplates a similar plan. Senator Paul Simon of Illinois proposes a guaranteed job opportunity program, subsidized with welfare savings.