Earlier in the day, Trump had responded to Obama's barrage by mocking the former president over what he described as a "very small crowd" in Miami.
Obama, who also spoke in Florida on Friday, called on voters to turn out for Democrat candidates and denounced efforts by Republicans to dismantle his political legacy.
Obama also criticized Donald Trump's plan to send active-duty troops to the US-Mexico border to assist Border Patrol agents, calling it a "political stunt at the border".
Obama campaigned in Florida and Georgia for Democratic candidates in two of the key races in Tuesday's midterm elections.
The final weekend of campaigning in the midterms might come down to this: Donald Trump versus Barack Obama.
"That's why I'm here", Trump said.
"You have a president that's going to be here today and you have an entertainer that's in office right now", said Rashawn Watson, a Democrat from Miami Gardens.
He has called the caravan an "invasion" and his administration recently authorized a plan to send several thousand troops to the U.S. border.
Trump is rallying in support of Republican gubernatorial candidate Ron DeSantis and Senate candidate Rick Scott, who are facing tough challenges in Tuesday's elections.More news: Michael Cohen Makes Explosive Claims Regarding Trump
Yet it landed at the end of a week in which the president has made immigration and border security the paramount issue for Republicans in the midterms, warning without offering evidence that a caravan of immigrants is preparing an "invasion" of the US southern border.
Republican Rep. Kevin Yoder of Kansas, a loyal supporter of White House policies who's at risk of losing his seat in the Kansas City area, recently suggested his Democratic opponent, Sharice Davids, may not "actually stand up to President Trump", the Kansas City Star reported.
In the absence of an obvious successor, former President Barack Obama has been the Democrat's star performer with his calls for a more inclusive kind of politics.
During his IN rally, Trump said he and Hall of Fame basketball coach Bob Knight had developed a "great romance".
You can also vote in person on Election Day, November 6, at your assigned precinct from 7 a.m.to 7 p.m.
"Who voted?" Trump asked the packed arena. "He's talking about how I should be nice to the fake news", Trump said.
Trump also defended his decision to focus nearly exclusively on the migrants and immigration in the closing days of the election.
In West Virginia, Trump's third visit in three months was aimed at shoring up Patrick Morrisey, who is seeking to unseat Democratic Senator Joe Manchin.