Mitt Romney this morning said that he has been paying close to 15 percent on his income taxes in recent years, a figure that is likely to be used by his political opponents to cast the former Massachusetts governor as out of touch with average Americans, many of whom pay at a much higher rate. “What’s the effective rate I’ve been paying?” Romney, who has declined to release his tax returns, said at a press conference here. “It’s probably closer to the 15 percent rate than anything. Because my last 10 years, I’ve -- my income comes overwhelmingly from some investments made in the past, whether ordinary income or earned annually.”