Because of people like you.
Well, and because people like me.
Barack Obama isn't a perfect president, nor is he even a perfect man. We've yet to see one of either. But he does represent the Democratic party, and while I don't totally agree with some of the things they say and do, in the end my political leanings align most closely with that group.
I support animal rights, environmental protections, and the use of cleaner, more renewable forms of energy. I support "going green." I oppose corporate lobbying and the idea that corporations are individuals. I vehemently oppose big oil. I support taxation. I support campaign finance reform. I support regulating Wall Street. I support scaling back the military and ending our involvement in Iraq and Afghanistan. I'm pro-choice. I support gay marriage rights. I support investing in healthcare, education, agriculture, science and technology, and the arts, and I believe those areas should take special priority.
In the last election, I didn't see those values on the GOP and Mitt Romney's side of the line. Obviously, not all of these values became initiatives in President Obama's first term, but a lot of them did. This is why I voted the way I did.
I'm not going to delude myself into thinking that the president, Republican or Democrat, will ever be wholly a success or wholly a failure. Nor will I suggest that the president stands alone in any continuing evaluation of the successes and failures of federal government. Finally, I will never apologize for who I vote for, or believe that my vote somehow represents a personal failure for America, any more than I'd expect others to do the same.