Paul, the son of three-time presidential candidate Ron Paul, will join New Jersey Gov. Chris Christie and former Republican presidential candidates Rick Santorum and Michele Bachmann at the day-long conference.
Elected in 2010 with robust support from the tea party, Paul represents the libertarian-leaning wing of the movement.
"Senator Paul is among America's most strident advocates for small government and individual liberty in the United States Senate," said ACU Chairman Al Cardenas. "We are proud to welcome Senator Paul to Chicago this summer as conservatives take the fight for the future of our country directly to President Barack Obama's backyard."
The conference, co-sponsored by The Heartland Institute and Right Nation, is the second regional gathering of conservative activists beyond ACU's annual meeting in Washington, D.C.
According to the latest schedule, businessman Foster Friess, who bankrolled the super PAC supporting Santorum's presidential campaign, will kick off the event after remarks from Cardenas, followed by speeches from Louisiana Gov. Bobby Jindal and Indiana State Treasurer Richard Mourdock, who is challenging Sen. Dick Lugar in a primary on Tuesday. Ohio Sen. Rob Portman, a possible vice presidential pick, has also been invited.
When Paul was asked about the possibility that he will be chosen as a vice presidential running mate to Mitt Romney earlier this year, he said he would be "an honor" to be considered, although it is still too early to tell who is on Romney's list of prospective running mates.
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