DETROIT (AP) — Days before a pivotal primary, Republican presidential candidate Mitt Romney said Friday he would raise the eligibility age for Medicare as he looks to show he's willing to curtail government benefits in the long run.

It was a new detail in a major campaign speech that was otherwise short on new policy ideas. Romney delivered the speech to the Detroit Economic Club at the cavernous and largely empty Ford Field, where the Detroit Lions play football.

"With these commonsense changes, we will have fixed our balance sheet," Romney told the crowd of about 1200, who occupied just a portion of the field itself as tens of thousands of stadium seats sat empty.