If you do not have the money mail 1st Class, but need First Class delivery speed, you can take advantage of PVDS or Priority Drop Ship.  For example:

Mailing consists of 1,513 pieces destined for Hawaii

Costs and Savings 

• Standard Non Profit Mail: $157
• Priority Mail & Handling: $122
• Total Costs:  $278.74
• 1st Class Mail:  $559
• Net Savings:  $281

The mail is delivered within seven days of mailing.  Priority Mail arrives in two to three days to  Honolulu.  USPS delivers to houses/business two to four days later.