MORRISVILLE, N.C. — Wooing young voters, President Barack Obama is on a blitz to keep the cost of college loans from soaring for millions of students, taking his message to three states strategically important to his re-election bid. By taking on student debt, Obama is speaking to middle-class America and targeting an enormous burden that threatens the economic recovery.

Before Obama got his road trip under way, Republican opponent Mitt Romney found a way to steal some thunder from the president’s campaign argument: He agreed with it.

The competitors are now on record for freezing the current interest rates on a popular federal loan for poorer and middle-class students. The issue is looming because the rate will double from 3.4 percent to 6.8 percent on July 1 without intervention by Congress, an expiration date chosen in 2007 when a Democratic Congress voted to chop the rate in half.

Obama is heading to campuses in the South, West and Midwest to sell his message to colleges audiences bound to support it. As he pressures Republicans in Congress to act, he will also be trying to energize the young people essential to his campaign — those who voted for him last time and the many more who have turned voting age since then.

The president speaks Tuesday at the University of North Carolina at Chapel Hill and the University of Colorado at Boulder, and then the University of Iowa on Wednesday. All three universities are in states that Obama carried in 2008, and all three states are considered among the several that could swing to Obama or Romney and help decide a close 2012 election.