So she won't cut benefits, raise the retirement age, or increase payroll taxes? If such statements are to be taken at face value -- which they aren't, but leave that aside -- that leaves some combination of increasing or removing the income cap, extending the tax to unearned income, or general revenue financing.
All of these options, of course, further reduce the linkage between Social Security "contributions" and benefits. That linkage is already so tenuous that only the dim take it seriously, but at some point the mythology will collapse utterly and this brings that point nearer. The endgame for Hillary's apparent strategy is a means-tested old wage welfare system.
Sphinx,
You may have nailed it, For her "according to their means" is a tape that cannot be erased in her Marxist brain.
However, I could see her removing the earnings cap ($90k-ish) that is taxable. This would fit into her desire to play out the class warfare card.
What is funny is she has abandoned her husband's privatization "scheme" (Greenspan nixed it, to much gov't control :-), no freedom of choice) yet her program would have the guberment yielding total control. Man is she a control freak or what?