With Donald Trump's win in Indiana on Tuesday night, it would appear all doubt is gone. He is on his way to the Republican presidential nomination.

Ted Cruz came in second, and suspended his campaign shortly after the results came in. Only John Kasich is left to oppose Trump, but he has no clear path to the nomination.

"We'll also have to see where Republicans line up behind Trump," said John Dickerson, host of "Face the Nation" and CBS News political director. "There are some who are still in the Never Trump camp."

On the Democratic side, Bernie Sanders trails Hillary Clinton by about 800 delegates and that won't change much even though he won the Indiana primary.

That means it will likely be Trump versus Clinton in the general election.

"It might not be very pretty," Dickerson said about that match-up. "We have two candidates here who are at historic negatives in terms of the public's view."

Dickerson noted that Trump has already begun attacking Clinton for her gender. "That starts on a very negative note, and it may just stay there in this race. It looks a little dark at the moment."

To see what else Dickerson had to say, watch the video above.