Can you imagine the news articles and headlines and what all would have been said if the Republicans, unhappy with Obama's election and/or re-election, had of called for his impeachment due to any of several reasons or times he disregarded the constitution? How about when he outright lied about the Benghazi attack saying it was a YouTube video that caused it all the time knowing different. He was afraid it was going to affect his reelection bid. That's just one offense but many times he usurped powers that were never given to the President, by the Constitution and many were in horror and upset about his election yet no one was deranged enough to call for impeachment every day.
If they had, though, you know what the mantra would have been and what would have been touted from floor to ceiling of every newsroom. Racism ... Racism ... Racism. People would be said to be racist because they disagreed with Obama, his policies, or what he was doing. It was almost Guarnteed to come from the Democrats and the Press/media. Today Democrats are looking for anything to oppose Trump on and manufacturing things in order to try and form a bloodless coup and impeach him. Thank God they don't have the House and run the Senate but that very well could change later in this year and in great part to the ineffectual Republican Senate.
The House has passed a lot of legislation that has died in the Senate account of Senate Republican leadership (or lack of it). The Senate Republicans are squandering, at an unprecedented level, opportunities to grow their base and do good for the nation.