I don't know what they have in mind, but that sounds like something you could do by improving income inequality. The top decile gets half the income. If you redistribute half of that, you can double the income of the bottom 60%. If you allocate that new money on a flat per-household basis, the high end gets something like a 50% boost, and at the low end you have millions of people in deep poverty getting more than a 500% boost.

Obviously that exact distribution is flawed, but I think it gets the point across.