I have always thought that Barack Obama's nomination of Merrick Garland for the Supreme Court was nothing but a political move. While Garland is "supremely" qualified, he is too moderate for either Barack Obama's or Hillary Clinton's tastes. Don't be surprised if his nomination is pulled by Obama if Hillary wins, thereby leaving the nomination process in her hands. If the Senate flips to Democratic control, there will be nothing stopping her from seating a young, far left nominee that will affect the high court for decades to come.
Both Obama and Hillary are very aware of what the Supreme Court means to an extremely liberal administration. The very left-leaning Obama and his "pen" actions on executive orders have yielded just a 45% win rate in the court. Compare that to an average win rate of more than 60% for all other administrations in the last 50 years. Obama was so liberal that the 4 liberal Justices on the court sided with their conservative counterparts by handing down a total of 44 unanimous decisions against him.
The Republican Senate probably made a horrible tactical decision by not approving the appointment of Garland; especially since they have known for months that a potential loser like Trump was their party's nominee. Now, there is a distinct possibility that the first liberal court since before 1970, can wind up being more extreme than ever imagined. At stake will be decisions on gun control, late term abortions, extreme air and clean water rulings, and every liberal direction Hillary Clinton can take us. When she takes office, she will quickly begin her run for a second term, by showing her suppporters that she means to take care of business for them. A more liberal Supreme Court will assist by not blocking her actions.
Merrick Garland’s instinct for the middle could put him in the court’s most influential spot: https://www.washingtonpost.com/politics/courts_law/merrick-garlands-instinct-is-for-the-middle/2016/03/16/59a82132-eb91-11e5-a6f3-21ccdbc5f74e_story.html?tid=a_inl
What If the Supreme Court Were Liberal?: http://www.theatlantic.com/politics/archive/2016/04/what-if-the-supreme-court-were-liberal/477018/
Obama Has Lost In The Supreme Court More Than Any Modern President: http://thefederalist.com/2016/07/06/obama-has-lost-in-the-supreme-court-more-than-any-modern-president/
After 45 years of conservative rulings, here’s what a liberal Supreme Court would do: https://www.washingtonpost.com/opinions/after-45-years-of-conservative-rulings-heres-what-a-liberal-supreme-court-would-do/2016/02/19/efa63ad4-d589-11e5-b195-2e29a4e13425_story.html?utm_term=.457a9e4162ae