Republican presidential candidates have been holding mock debates, hunkering down with advisers and finessing policy answers. But their most pressing concern heading into the first debate of the 2016 presidential primary season is one man: Donald Trump.

The billionaire businessman has dominated the primary race in recent weeks. He’s expected to play an outsized role on national television when the top 10 Republican candidates face each other for the first time on national television on Aug. 6.

It’s a high-risk, high-reward event for candidates eager to stand out in a packed field in which Trump is playing the ultimate wildcard.

Some veteran political operatives suggest that the candidates ignore Trump. Others suggest that they confront him.

All agree that Trump needs to be dealt with very carefully.

(AP)