At Republican Debate, Candidates Are Likely to Set Sights on Ted Cruz

In the five weeks since the last Republican presidential debate, terrorists have struck in Paris and San Bernardino, Calif., Donald J. Trump has proposed barring Muslims from coming to America, Ben Carson’s support has evaporated and Senator Ted Cruz of Texas has emerged as Mr. Trump’s stiffest competition. Senator Marco Rubio of Florida has gone on the attack against Mr. Cruz, and Gov. Chris Christie of New Jersey, who has less money than many senators up for re-election, has shown signs of life, at least in New Hampshire.