Republican presidential candidate Donald Trump is heading to the backyard of rival John Kasich Monday night after a tumultuous week of dubious claims about Muslims and fisticuffs at an Alabama rally. The Ohio governor wants to use the event to derail him.

Trump is speaking at a Columbus event blocks from Kasich's office after drawing criticism in recent days for advocating the tracking of Muslims and suggesting that Islamic crowds in New Jersey cheered the collapse of the World Trade Center towers, an assertion for which there is no proof.

While Trump continues to lead polls for the Republican nomination, Kasich is part of a stepped-up effort seeking to paint the real-estate mogul as unprepared to lead and unable to defeat Democrat Hillary Rodham Clinton. Kasich's super-PAC, which is spending $2.5 million on a New Hampshire ad campaign targeting Trump, says it is attracting donors supporting other presidential candidates to help with the attacks.