WASHINGTON (NEXSTAR) – It was a busy night on the campaign trail.  The candidates are focusing their attention on seven key states in this election. The campaigns had events in Nevada, Arizona, Michigan, Pennsylvania and North Carolina and for the first time this year, Vice President Kamala Harris called on the 44th president to try to convince voters to make her the 47th. Former president Donald Trump was in Detroit. “Under Biden and Harris, because of inflation, the economy has been a total disaster,” said Trump. Senator JD Vance (R-Ohio.) spoke at a town hall in North Carolina. “The most important thing we gotta do to lower prices and make life more affordable, is drill, baby, drill,” said Vance. In Arizona, a state President Joe Biden won by 10,000 votes, Vice President Kamala Harris talked about her plan to lower costs. “Taking on for example the issue of corporate price gouging. I've done it before and I'm going to do it again,” said Harris. Nearly eight years after he left office, former president Barack Obama took credit for the Trump economy. “I remember that economy when he first came in being pretty good. Yeah, it was pretty good. Because it was my economy,” said Obama. With less than a month to go before the election, the rallies included talk of policy and personal attacks. “Our whole country will end up being like Detroit, if she's your president. You're going to have a mess on your hands,” said Trump. Meanwhile Obama said, “There is absolutely no evidence that this man thinks about anybody but himself.” Friday afternoon former president Donald Trump will hold a rally in Aurora, Colorado.  The city gained national attention because of a video showing armed men walking through an apartment building housing Venezuelan migrants, again zeroing in on one of his key campaign issues of immigration. Vice President Harris is headed back to Washington.