The GOP nominee has also lashed out at Republicans he claims have been "disloyal." House Speaker Paul Ryan has said he would no longer defend Trump in the wake of a 2005 video showing Trump bragging about groping women. Other big-name Republicans have also announced they were withdrawing their support.
While Trump's troubles could pull support away from other Republican candidates, voters may also opt to pull the lever for Trump and ignore those who are not supporting him, said Pethokoukis, who is also a CNBC contributor.
Now Democrats "are talking about a clean sweep and being able to re-run the first term of Obama the way they would have liked to have done if it wasn't overshadowed by the financial crisis," he said.
That means things like the return of cap and trade, which is geared toward controlling greenhouse gas emissions, executive pay reform, paid leave and the Pacific Trade Deal, he noted.
He also thinks it may mean reforms in Obamacare and perhaps spending more money on it, as well as Clinton's tax hikes going through.