Trump calls Gavin Newsom a 'clown' during rally; Newsom compares Trump to Pennywise in response

President Donald Trump speaks during a "Make America Great Again" rally in Las Vegas on Sept. 20, 2018. President Donald Trump speaks during a "Make America Great Again" rally in Las Vegas on Sept. 20, 2018. Photo: MANDEL NGAN;Mandel Ngan / AFP / Getty Images Photo: MANDEL NGAN;Mandel Ngan / AFP / Getty Images Image 1 of / 22 Caption Close Trump calls Gavin Newsom a 'clown' during rally; Newsom compares Trump to Pennywise in response 1 / 22 Back to Gallery

For the second time this month, President Donald Trump called out California gubernatorial candidate Gavin Newsom during a campaign rally, and the former mayor of San Francisco responded.

During a Thursday night rally in Nevada for incumbent Republican Sen. Dean Heller, Trump called Newsom a "clown" who "wants open borders."

"Democrats want to give welfare and free health care to illegal aliens," Trump said. "How about this clown in California who's running for governor? He wants open borders and then he wants to give them health care, education, everything."

"Democrats want to give welfare and free health care to illegal aliens," Trump says to boos, adding of Gavin Newsom, "How about this clown in California who's running for governor?" — Daniel Dale (@ddale8) September 21, 2018 .@realDonaldTrump also took a shot at @GavinNewsom. “How about this clown who’s running for governor in California? He wants open borders and then he wants to give them health care, education, everything.” — Ramona Giwargis (@RamonaGiwargis) September 21, 2018

After the rally concluded, Newsom took to Twitter to compare Trump to Pennywise, the villainous clown in Stephen King's "It."

"lol, hi @realDonaldTrump," Newsom tweeted with a clown emoji. "Interesting description coming from the guy who is literally locking up kids like Pennywise."

lol, hi @realDonaldTrump.



Interesting description coming from the guy who is literally locking up kids like Pennywise. pic.twitter.com/bt49kyGk9Z — Gavin Newsom (@GavinNewsom) September 21, 2018

MORE NEWSOM: Gavin Newsom finally addresses Kimberly Guilfoyle's relationship with Donald Trump Jr.

Newsom has been a vocal critic of the Trump administration's policy of separating children from their parents at the border. In "It," an ancient demon takes the form of a clown named Pennywise and feasts on the fears of children.

Two weeks ago, Trump took aim at Newsom for his proposal to to have California pay for universal health care for state's undocumented immigrants.

"How about the governor, governorship of California," Trump said in an attempt to refer to Newsom. "He just announced that he wants to open borders, and he wants to let anybody come in that wants to. And then he wants to pay for all medical, all school."

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Newsom fired back with, "Hey, @realDonaldTrump -- Next time you call me and my policies out, have the guts to @ me and we can have a chat."

Eric Ting is an SFGATE staff writer. Email him at eting@sfchronicle.com and follow him on Twitter