(AP) -- Donald Trump should retract comments he made about a federal judge's Mexican heritage, a spokesman for Republican Sen. Ron Johnson said Monday.
Johnson became the latest Republican to criticize Trump for saying he believed a Latino judge presiding over a lawsuit against Trump University could not be fair because of his ethnic background. Others calling for Trump to apologize included his former rivals, Ohio Gov. John Kasich and Florida Sen. Marco Rubio.
House Speaker Paul Ryan, of Janesville, last week said he "completely disagreed" with Trump.
Johnson's call for Trump to retract the comments came after a spokesman for his Democratic challenger, Russ Feingold, earlier Monday said Johnson should immediately condemn Trump.
"Ron disagrees, just as he has in the past," Johnson spokesman Brian Reisinger said of Trump's comments in a prepared statement. Johnson has been critical of Trump's proposal to ban all Muslims from entering the country. But Johnson says he supports Trump for president, but says that's different from endorsing him.
"Ron will hold both candidates accountable when they're wrong, and there will be plenty of opportunities to do so with a Washington career politician like Hillary Clinton," Reisinger said.
Feingold spokesman Michael Tyler noted that Johnson had previously said if Trump said or did anything that "crosses a line and in the end is so significant, so major you couldn't support them" he would withdraw his support.
"It's clear from his response that racist comments from Trump don't rise to that level for Sen. Johnson," Tyler said.
Johnson and Feingold are locked in a rematch of the 2010 race that Johnson won. It's expected to be one of the fiercest-fought Senate campaigns nationwide, with Democrats eyeing the seat as one they can pick up as they try to regain majority control of the Senate.
Trump showed no signs of backing down. He insisted earlier Monday that his criticism of the judge came in defense against relentless questions from reporters and others about lawsuits against Trump University. Trump said U.S. District Judge Gonzalo Curiel can't be impartial in the lawsuits because the jurist's parents were born in Mexico and Trump wants to build a wall along the U.S.-Mexico border. Last week, he denied on CNN that his remarks are racist.