U.S. Sen. Ron Johnson is standing by Donald Trump, even as polls show the Wisconsin Republican trailing Democratic challenger Russ Feingold.
Northern Illinois University political scientist Matt Streb is watching this race closely. He says Sen. Johnson is limited to two difficult choices with Trump on the ballot.
"To back out of your support for him isn't going to be seen positively by independents," Streb says, "and it's going to do nothing but upset your base, so I think that's one reason you're seeing Johnson double down here."
Streb says Democrats need a net gain of five seats to take control of the Senate. That margin drops to four seats if Hillary Clinton wins the Presidency, which would allow her vice president to cast tie-breaking votes.
Both scenarios depend, according to Streb, on Democrats winning the Illinois and Wisconsin U.S. Senate seats.
Meanwhile, the U.S. House also appears to be in play. Speaker Paul Ryan, of Wisconsin's Congressional District 1, recently let members of the Republican caucus go their own way regarding Trump. Members can support their presidential nominee or attack him – whatever it takes to get re-elected. Many experts view this as a sign that Ryan is concerned about losing the lower chamber.
Democrats need a net gain of 30 seats for a House majority, which Streb says is an uphill battle.
"As of today, there are about 20 seats that they could potentially pick up," Streb says. "And they'd have to run the table on those seats. So you'd still be a little short."
Matt Streb will join the WNIJ News team for live Election Night updates after the polls close on Nov. 8.