In general, State is saying routine processing is 18+ weeks, 12+ weeks for expedited. That timing is more the case than not, but there sporadic posts here of folks reporting receiving it back in about 6 weeks. It basically depends on what processing center your application was sent to - no real way to choose beforehand or change it after it has been submitted. So, you will almost assuredly need intervention from your congressional representative or senator.

First, sign up for the emailed processing status notifications. Second, did you request expedited processing? If not, call the passport center and request and pay for an "upgrade" to expedited processing. Then, about 3-4 weeks before your travel date, contact one of your congressional reps and ask them to check on it for you. They will need you to complete a form authorizing them to intercede on your behalf. They may be able to get it processed and mailed faster or they may be able to get you an in-person appointment within 72 hours of your flight. Be patient, be flexible.