ORLANDO, Fla. (Reuters) - President Donald Trump formally launched his 2020 re-election campaign on Tuesday by presenting himself as the same political insurgent who shook up the Washington establishment four years ago and who is now a victim of an attempted ouster by Democrats.

At a packed rally at an arena in Orlando, Florida, Trump made clear he would run for re-election as an outsider, just as he did in 2016. Whether he can pull it off remains far from certain as Trump has been in office now for 2-1/2 years.

He revisited campaign themes from four years ago, decrying illegal immigration, the news media and his 2016 Democratic opponent, Hillary Clinton.

“Together we stared down a broken political establishment and we restored government by and for the people,” Trump said. “As long as you keep this team in place, we have a tremendous way to go. Our future has never looked brighter or sharper.”

Trump said his Democratic challengers would radically change the United States and seek to legalize migrants coming across the southern border so they could vote and boost the Democratic political base.

Democrats “want to destroy our country as we know it” and that it’s “not going to happen,” Trump said.

“We believe our country should be a sanctuary for law-abiding citizens, not for criminal aliens,” he said.

Two dozen Democrats are competing for their party’s nomination to face off against Trump in the November 2020 election. Many of the top Democrats lead Trump in opinion polls in battleground states.

Trump called his opponents a “radical left-wing mob” who would bring socialism to the United States.

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“A vote for any Democrat in 2020 is a vote for the rise of radical socialism and the destruction of the American dream,” he said.

AIRING GRIEVANCES

Trump made his re-election launch official at what was his 60th political rally since he took office in January 2017. He brought his wife, Melania, and a large contingent of senior White House staff.

“Tonight I stand before you to officially launch my campaign for a second term as president of the United States,” Trump said. “I promise you I will never ever let you down.”

Over the course of a speech that lasted an hour and 20 minutes, Trump blasted the news media as “fake news,” took credit for a strong economy, said he was putting the heat on China on trade, promoted his proposal for a “space force,” vowed to protect Americans’ rights to own guns and said he wanted to launch a space mission to Mars.

Trump also declared himself a victim and aired his grievances.

He made an issue of Special Counsel Robert Mueller’s investigation into Russian interference in the 2016 election. The probe found insufficient evidence to establish that the Trump campaign engaged in a criminal conspiracy with Moscow. It also described numerous attempts by Trump to impede Mueller’s probe, but stopped short of declaring that he committed a crime.

“We went through the biggest witch hunt in political history,” said Trump. “It was all an illegal attempt to overturn the results of the election.”

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Two-and-a-half years into his tenure, Trump sees plenty of positive factors, led by a growing economy with low unemployment.

“If the economy stays strong, he is very likely to get re-elected,” said Trump confidant Newt Gingrich, a former Republican speaker of the U.S. House of Representatives.

But the lingering aftermath of the Russia probe, coupled with a presidential style marked by name-calling and eye-popping tweets, has undermined some Americans’ confidence in Trump.

He also has stirred division with his hard-line policies on immigration and unsettled business and farm groups with his use of tariffs in trade disputes with China and some allies.

Democrats cite a string of broken promises in Trump’s first term, from lowering drug prices to closing corporate tax loopholes and stopping plant closures.

“Donald Trump is launching his campaign for re-election tonight and the American people face a choice - we can make Trump an aberration or let him fundamentally and forever alter the character of this nation,” said Kate Bedingfield, deputy campaign manager for Democratic front-runner Joe Biden.

POLLING CONCERNS

A Reuters/Ipsos poll on June 11 gave Trump a 40% job approval rating, compared with 57% who disapproved. Other opinion polls have shown him running consistently behind his main Democratic challengers, such as Biden, in key battleground states.

Republican strategists say the fundamentals favor Trump as he heads into his election but that he faces challenges given his bare-knuckled approach, which he refuses to temper.

The Orlando Sentinel welcomed the president’s visit with an editorial titled: “Our endorsement for president in 2020: Not Donald Trump.”

Trump supporters with tents and sleeping bags started camping out at the rally venue on Monday and thousands had gathered by Tuesday afternoon in a torrential downpour. “It was like a big Trump party,” said Maureen Bailey, who slept in a tent with her twin sister, Laureen Vartanian.