Dealing with seedlings that are healthy but extremely leggy

My tomato seedlings look green and healthy but have stretched into thin stems that lean toward the window. They're probably too far from the light. I can move a lamp closer, but I'm unsure whether the current seedlings will become sturdy once conditions improve or if I should start again. They have their first true leaves, and transplanting time is still a few weeks away. Has anyone successfully rescued leggy seedlings without burying them ridiculously deep?