President Donald Trump on Wednesday released an ad that blames Democrats for the case of a an unauthorized immigrant who killed multiple police officers in 2014.

Many saw comparisons between Trump's new ad and the infamous "Willie Horton" ads that ran in support of former President George H.W. Bush against Michael Dukakis in 1988.

President Donald Trump on Wednesday released an ad that blamed Democrats for a homicidal unauthorized immigrant, stirring outrage for its overt racial themes days before the midterm elections.

The ad prominently features Luis Bracamontes, an unauthorized Mexican immigrant who was given the death penalty in April for killing two California cops in 2014. The ad depicts Bracamontes as the poster child for unauthorized immigration and falsely claims "Democrats let him into our country ... Democrats let him stay."

Bracamontes was deported twice for entering the country illegally. When he committed the killings in 2014, he was also not authorized to be in the US.

The first time Bracamontes was deported was in 1997 under the Clinton administration. A year later, Bracamontes was back in the US and got arrested on a drug charge in Phoenix. He was released for "unknown reasons" under Sheriff Joe Arpaio's custody and continued to live in the US for several more years, Yahoo News reports.

Arpaio, 85, is a controversial figure with close ties to the president. Trump pardoned Arpaio earlier this year after he was found guilty of criminal contempt for violating the terms of a 2011 court order in a racial profiling case. The former sheriff has often come under fire for his incendiary views on undocumented immigration and gained notoriety for his "tent city jail," which was described by some as a "concentration camp."

Bracamontes' second deportation occurred in 2001, during the first year of the Bush administration. Bracamontes managed to enter the country illegally again in 2002, while former President George W. Bush was still in office, and somehow avoided deportation until his eventual arrest for killing the two California police officers.

Trump's new ad also includes clips of unidentified people rioting in unspecified locations, seemingly portraying a migrant caravan heading toward the US border as inherently violent and anarchic.

The president has repeatedly claimed, without providing evidence, that the caravan is full of dangerous criminals and possibly people from the Middle East.

The ad ends with the question, "Who else would Democrats let in? President Donald Trump and Republicans are making America safe again."

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Critics and other observers, including some conservatives, decried the ad as blatantly "racist." Republican Sen. Jeff Flake called the ad "sickening" and "a new low in campaigning."

It wasn't the first time Trump has used Bracamontes' story in an ad. A January ad also featured him and accused Democrats of being "complicit in all murders" by unauthorized immigrants.

Many drew comparisons to the infamous "Willie Horton" ads that ran in support of former President George H.W. Bush against then-Massachusetts Gov. Michael Dukakis in 1988.

William Horton, who was dubbed "Willie Horton," was a convicted murderer serving a life sentence who was permitted to leave prison in June 1986 via a weekend furlough program in Massachusetts. Horton absconded during furlough and in April 1987 raped a white woman and stabbed her white fiancée, according to The Washington Post. As governor, Dukakis supported the furlough program.

At the time, crime was at the forefront of American voter's minds, as brutal drug-related violence was a common occurrence in major American cities like New York City, Los Angeles, and Washington, DC.

Supporters of Bush seized on these sentiments by creating ads that either alluded to or directly referenced Horton's story. One of the ads featured Horton's mugshot, while another portrayed Dukakis as someone who favors prisons with revolving doors. The latter was produced by Roger Ailes, who founded Fox News. However, the Bush campaign did not directly produce the ads.