AXIOS (Kate Santaliz) - GOP fight to replace McConnell turns ugly over immigration
The race to replace retiring former Senate Majority Leader Mitch McConnell (R-Ky.) has turned ugly over immigration . Why it matters: The seat is safely Republican, but the primary is shaping up to be one of the cycle's most bruising intra-party battles. - Rep. Andy Barr (R-Ky.), former Attorney General Daniel Cameron and businessman Nate Morris are leading contenders. - Though none has secured President Trump's endorsement. Driving the news: A Club for Growth-aligned super PAC, Win It Back, launched a new TV ad titled "Amnesty Andy" targeting Barr over immigration. - "In México, they call him Amnesty Andy and illegal aliens' best amigo," a narrator says in the ad . - In under a week, Win it Back PAC dropped nearly $750,000 on the…