The Republican candidates for Governor haven't highlighted the issue of health care [1] access because they don't care whether coverage expands or not. They are fine with the health care access backsliding fostered by the Blunt administration and the current levels of uninsured Missourians.
Expecting the GOP candidates to campaign on health care is a bit like expecting Jay Nixon to campaign on the idea that Ronnie Reagan's face should appear on the dime; it's foolish because that's just not something Democrats see as a priority.
Draw from that whatever conclusions you will.