MIAMI - US Senator Marco Rubio is looking to sell his house in the Miami neighborhood he cited in his closely watched response to President Barack Obama's State of the Union speech.The first-term Republican senator from Florida played up his humble upbringing when he delivered the Republican Party rebuttal to Obama's address on Tuesday, pointing to a Miami neighborhood where he was born and raised and now resides."Mr. President, I still live in the same working-class neighborhood I grew up in," Rubio said, trying to highlight his modest roots as he laid out the alternative Republican vision for helping the middle class.