The co-chairs of the House Progressive Caucus have sent President Obama a letter vowing to reject healthcare reform legislation that doesn’t include a public option based on Medicare rates. In the letter, Democratic Congress members Lynn Woolsey of California and Raul Grijalva of Arizona write, “A health reform bill without a robust public option will not achieve the health reform this country so desperately needs. We cannot vote for anything less.” The letter follows reports the White House has privately revived a plan that would “trigger” a public option only if private insurers are deemed to have not provided suitable care and market competition.