Standing next to Rubio, Romney demurs on VP search

ASTON, Pa. — Republican Mitt Romney has declined to endorse an immigration proposal from potential running mate Marco Rubio and says he's looking at the senator's plan.

Standing with Rubio in Aston, Pa., the presumptive Republican presidential nominee didn't come down one way or the other on Rubio's proposal.

Romney also wouldn't talk about running mates. He said he's just starting the process of identifying a vice presidential candidate, and is working with his attorneys and accountants.

Romney answered reporters' questions Monday for the first time since effectively securing the Republicans' presidential nomination.

He also said he supports extending low interest rates on student loans, which President Barack Obama has been pressing Congress to do.