The Senate wasn't hand-picked by Obama. Fuck, many of them had been in the Senate longer than Obama had been in politics, repeatedly re-elected by their constituents to represent interests which were not necessarily in-line with Obama's plans. "He should have just done it better!" is a ridiculous position.
His team is the Democratic Party because there are two major parties in this country. And one of them spent years calling him racial slurs, so their support was doubtful.
What were Obama's other choices, in this scenario?
We fight according to the situation as it is, not the situation as we want it to be.
An incredibly popular president returning after having already been elected once split off during a contested convention at the Republican Party, which was initially the venue through which their candidate was going to run and managed to lose the ensuing election, accomplishing nothing except the election of a rival.
And that was the best third-party showing in US presidential history.