A group of Republican senators fighting for their political lives are barely touching what could be Democrats’ most uncomfortable topic this year: Obamacare.

In sharp contrast to past elections, GOP lawmakers aren’t making President Obama’s healthcare law a front-and-center issue. Yet it’s the first year they have actual proof the Affordable Care Act isn’t working as well as its supporters had hoped, as insurers seek double-digit price hikes and exit the marketplaces due to heavy losses.