Reid rips Grassley over Trump
"I believe no member of the Senate has done more for Trump than the chairman of the Senate Judiciary Committee," Reid said from the Senate floor. "At every turn, the senior senator from Iowa used his committee for partisan purposes that benefit only one person: Donald Trump." 
Reid's comments come as Republicans increasingly distance themselves from Trump's comments that U.S. District Judge Gonzalo Curiel has "an absolute conflict" in presiding over fraud lawsuits against Trump University because of his Mexican heritage.
Grassley told Roll Call on Monday that Trump's comments shouldn't raise concerns about potential judicial nominations he would make and that the Senate would be a "check" on a hypothetical President TrumpDonald John TrumpSarah Huckabee Sanders becomes Fox News contributor The US-Iranian scuffle over a ship is a sideshow to events in the Gulf South Korea: US, North Korea to resume nuclear talks 'soon' MORE
Reid on Tuesday blasted Trump's comments as "racist and un-American," arguing Grassley, as chairman of the Judiciary Committee, should stand up for the court system. 
"Instead of rising above partisanship and condemning Trump's racist attacks on a highly qualified federal judge, Sen. Grassley kisses Trump's ring and toes the party line," Reid said.
"Instead of ... condemning Trump's racist attack, Grassley defended him. His rationale is boggling," Reid added. 
Reid also doubled down on his criticism of Grassley's probe into Democratic presidential front-runner Hillary ClintonHillary Diane Rodham ClintonPoll shows Biden, Warren tied with Trump in Arizona The Hill's Morning Report - Trump touts new immigration policy, backtracks on tax cuts Hickenlooper announces Senate bid MORE's private email server and a top aide, saying the committee has "spent its time carrying out a political hit job on Secretary Clinton." 
Democrats have been quick to criticize Republicans who have disavowed Trump's remarks on Curiel but still pledge to support him as the party's nominee. 
Reid grilled McConnell from the Senate floor on Monday afternoon and added Tuesday that Grassley should have to answer if he believes Trump's comments are racist. 
"After everything we've heard from Donald Trump, all of his vile, unhinged racism, does Sen. Grassley honestly have confidence that Donald Trump should pick the next Supreme Court nominee?" he said. 
"I can only tell you what I would do, and I wouldn’t say what Mr. Trump said,” Grassley said in a statement on Tuesday, noting that he supported Curiel in the Judiciary Committee and on the Senate floor.
“On the face of it, I disagree with his assessment, but I’m also not informed on all the facts of the case.”
— This report was updated at 12:33 p.m.