The upcoming election has received a lot of attention based on the controversial nature of both the Democratic and Republican nominees. The Republican nominee, Donald Trump, has garnered unexpected support and seen success in the polls that no one could have predicted. His success has caused a divide in the Republican party and won over voters and non-voters who had traditional democratic leanings. Together, these two adverse reactions set the perfect stage for the Republicans to maintain the senate majority. Thinking, or rather hoping that Trump will lose the election, Republicans, who may have voted the issues instead of a straight Republican ticket, may be less inclined to vote for qualified Democrats in order to ensure Republicans retain control. Conversely, first-time voters inspired by Trump's rhetoric and promises to "make America great again," are probably more likely to vote a straight Republican ticket for the sole reason that Trump represents the party. The confluence of these votes are likely to ensure that the senate remains under Republican control.
Yes, I think the Republicans will keep the Senate majority this year after the November election, regardless of which nominee wins the Presidency. The Republican presence in the Senate is just too strong, and I don't see them losing enough races to be in the minority during the next 2 years.
It looks increasingly likely that Republicans will lose their Senate majority this year. People no longer split the ticket. Instead, they vote along party lines. In this election, Democrat Hillary Clinton has a clear advantage in many states. This is helped by Donald Trump, who keeps making outrageous comments, hurting his party's chances in down ballot races.
Not only will Trump get trounced in the presidential election, he will bring Republicans up and down the ticket down with him. People are starting to see the party for what it is, and senators who back Trump are seeing their own poll numbers fall. People are tired of the hatred, and the Senate will change.