Donald Trump spoke at the Libertarian Party Convention on Saturday night and, given the controversy over the invitation within the party, it wasn't surprising that many in the audience expressed their displeasure at the former president's presence.

Trump was trying to pry some Libertarian Party voters away from Robert Kennedy. who spoke earlier in the day to a sparse crowd. 

Besides that, it took some courage to speak at a venue where he knew he would receive a mixed reception. Trump paid the crowd little mind, making his points and occasionally responding to the crowd.

"You can keep going the way you have for the last long decades and get your 3% and meet again, get another 3%," Trump said following jeers from the crowd. He was referring to the vote for the Libertarian Party president in the national election.

Trump also tried some humor to loosen up the crowd, referring to the four criminal cases against him. "If I wasn’t a Libertarian before, I sure as hell am a Libertarian now," he said.

There were more than a few "Make America Great" hats in the audience, and the former president received his share of cheers. But by and large, it was a hostile crowd that Trump faced down.

Fox News:

Libertarians, who value small government and individual freedoms, have long been critical of Trump, and his invitation to the convention divided the party, with some saying a candidate opposed to Libertarian values running for another party should not be welcomed because it would distract from Libertarian candidates and causes, while others praised the move because Trump's presence would bring media attention to the convention.

Entrepreneur Vivek Ramaswamy, who ran for president in the Republican primary before dropping out to endorse Trump, was another non-Libertarian in addition to Trump and Kennedy Jr. who spoke at the convention.

Ramaswamy also heard boos as he spoke on Friday when he mentioned Trump's name.

Despite the boos, Trump said he came "to extend a hand of friendship" in united opposition to the president. But many in the crowd were having none of it.

Chase Oliver of Georgia, a Libertarian Party presidential candidate. was none too pleased at Trump's appearance. "The truth is, I don't like having a war criminal on this stage, I don't feel he deserves a spot on this stage," Oliver said.

Several times, Trump asked for the party's endorsement or their votes. He was booed each time.

"I'm asking for the Libertarian Party's endorsement, or at least lots of your votes, lots and lots of Libertarian votes," Trump said to a chorus of boos.

That Trump came at all is an indication that he believes every vote is going to count.

“What he’s really trying to do is to show that he can be a president for all Americans,” a Trump campaign official said ahead of the former president’s remarks. “If you want to compete for nontraditional Republican votes, then you got to go where they are. You can’t expect them to just show up to you.”

Politicians usually don't go where they're likely to be booed. "Bad optics," you see. But in this case, Trump made a point to his supporters as well.

No matter what they do, they can't shut me up.