Former Gov. Mitt Romney came under new fire from all sides yesterday over his landmark Bay State health-care overhaul as potential 2012 Republican rivals and local Democrats took turns blasting the GOP presidential front-runner. “I’ve talked to residents of Massachusetts, and what I’ve gotten is that (health-care reform is) really not working well at all,” said former New Mexico Gov. Gary Johnson, who is believed to be considering a 2012 bid. Johnson declined to comment on whether health care will hurt Romney’s candidacy, saying, “whatever the criticism is about a candidate, everyone already knows it. I don’t (have to) say...