CHICAGO (AP) - There will be no knockout punch, but an increasingly confident Mitt Romney expects to tighten his grasp on the Republican presidential nomination with the Illinois primary.

Romney is surging in Illinois polls after the race was seen as a statistical tie just a week ago. He's riding momentum from a lopsided weekend victory in Puerto Rico punctuated by apparent missteps from rival rick Santorum on the eve of today's Illinois contest.

Romney's wife, Ann, has suggested in recent days that Illinois voters could send a strong message that now is the time to coalesce behind one candidate. Romney is eager to move beyond the expensive and extended Republican contest to focus on President Barack Obama in the general election. But he's struggled to win over skeptical conservatives.