Next year's election is still about a year away. And if history is any indicator, just about anything can and will happen.
Before the election, political leaders must first get through the Presidential impeachment process. No one knows how this thing will end but don't assume it's bad news for President Trump. Former President Bill Clinton became more popular after his impeachment.
Secondly, let's not forget that the Democratic field isn't even set yet, and history is filled with front runners who fizzled out.
Take Jeb Bush and Howard Dean for example. Both men were their parties' leading contenders before the primaries started, and neither were nominated for their parties.
Finally, what will be the big issue for voters? So far it seems like healthcare. Some Democrats pushing for Medicare for all. As for the President, he ran on repealing ObamaCare last time around. With twelve months to go, there could be a bigger, still unknown issue facing voters in one year.