The attempted assassination of former President Donald Trump has thoroughly altered the stakes and tone of the Republican National Convention in Milwaukee, which kicks off Monday, just two days after a shooter opened fire at the former president's Pennsylvania rally on Saturday, grazing Trump's ear and leading to a spectator's death.

Trump arrived in Milwaukee Sunday afternoon, ahead of the RNC's start on Monday.

In a social media post Sunday, Trump indicated that he was going to delay his trip, but decided he wouldn't allow a "shooter" to change his scheduled plans to head to the RNC.

U.S. Secret Service and other officials said Sunday there are no plans to expand the security perimeter and that there are no known threats. Ahead of the shooting at his rally, the GOP convention was gearing up to be an extravagant event centered around symbolic, Trump-era Republican ideas and party unity, sealed on Thursday with the third nomination of the former president.

-ABC's Brittany Shepherd, Kelsey Walsh and Isabella Murray

As the Republican National Convention begins, the atmosphere will feel entirely different following former President Donald Trump’s attempted assassination.

A day after being grazed by a bullet, Trump indicated he plans to take advantage of the moment and deliver a message of unity.

The former president said he is scratching his original convention speech from rallying his base against President Joe Biden to now attempting to draw the country together, according to an interview he did with the Washington Examiner conducted as he boarded his flight to Milwaukee Sunday evening.

During the first official session, delegates -- nearly 2,400 from across the nation -- must approve the committee platform and formally designate a presidential ticket. The ticket will include Trump’s vice president who he has yet to name.
The evening session's theme is "Make America Wealthy Again." Speeches will include issues focused on beating inflation, rising costs and creating more jobs.

-ABC's Kelsey Walsh