THE RACE for Philadelphia district attorney is shaping up to be both crowded and expensive.

Michael Untermeyer, a former assistant district attorney, has contributed $250,000 to his own campaign, triggering a doubling of contribution limits in the race, the Philadelphia Board of Ethics said Monday.

Untermeyer, 65, a real estate developer and businessman, is one of four Democrats challenging incumbent Seth Williams in the May primary. He also ran against Williams as a Republican in 2009.

The new limits are set at $6,000 for individuals and $23,800 for political committees and unincorporated business organizations.

The limits remain doubled even if Untermeyer drops out or his campaign refunds some or all of his money.

The other Democratic candidates are former Philadelphia Managing Director Rich Negrin, former Assistant District Attorney Joe Khan and Municipal Court Judge Teresa Carr Deni.

Beth Grossman, a 21-year veteran of the district attorney's office now in private practice, said she would run as a Republican.