Throughout the campaign, Democrats and the media took it as a given that their party would seize control of the Senate.

Democrats only needed to win four Senate seats according to a map tilted overwhelmingly in their favor.

But Donald Trump shocked political observers by creating a wave that carried Republicans to a victory experts thought was out of reach.

All the forecasters and pollsters saw the race for the Senate as extremely tight.

Most predictions had the Democrats winning four seats to create a 50-50 tie in the Chamber which they believed would be broken by Vice President Tim Kaine.

However, when the votes came in, all the predictions were wrong.

And it was largely because Donald Trump turned out voters the pollsters missed.

Incumbent Republican Ron Johnson – who was given up for dead by the pundits – won his race in Wisconsin because he had stood by Trump and campaigned with him.

When Trump won Wisconsin – which no Republican has done since 1984 – it carried Johnson across the finish line.

Politico reports:

“Indeed, even as late polls showed Republican Sen. Ron Johnson closing the margin with Democratic Sen. Russ Feingold, GOP strategists in Washington thought Johnson had a hard ceiling in the state.

More than any other vulnerable GOP Senate candidate, Johnson went all-in for Trump.

“Our nominee is a change agent,” Johnson declared in one debate with Feingold. “I’m a change agent.”

In the closing days of the campaign, Johnson joined Trump on the trail for the first time. (He and North Carolina’s Richard Burr were the only at-risk incumbents to do so.) And Johnson’s chances were boosted when Trump’s campaign aired $6.2 million in ads down the stretch in Wisconsin, while Clinton spent just $646,000 in the state.”

Missouri Senator Roy Blunt also faced problems.

Politico reports that Executive Director of the National Republican Senatorial Campaign Committee told his staff Blunt was on track to lose the race, but was saved by Trump’s strong performance in the Show Me State:

“We’re going to lose,” Baker responded. The NRSC executive director was firm, even though public polls still had Blunt ahead of Democratic Secretary of State Jason Kander.

The Missouri senator’s campaign didn’t take that news well. And two days later Democrats’ attacks on Blunt as a D.C. insider came into focus when Blunt was spotted at a farmer’s market in D.C.’s swanky Palisades neighborhood, instead of barnstorming Missouri.

Yet Trump ran so strongly in the conservative state that he pulled Blunt across the finish line, despite bipartisan praise for Kander as the best Senate candidate of the election cycle.”

A similar scenario played out in North Carolina where Republicans were concerned about Senator Richard Burr’s lackluster campaign schedule.

But Trump’s stronger-than-expected victory in North Carolina lifted him to victory as well.

Observers also noted that the Republican margin in the Senate would have been even stronger had all their candidates stood by Trump.

Senator Kelly Ayotte and Congressman Joe Heck – who was running for Harry Reid’s seat in Nevada – both announced they were not voting for Trump after the Access Hollywood tape of his lewd comments had been leaked.

Trump’s decisive victory allowed Republicans to retain a 52-48 majority in the Senate, and it creates a situation where the GOP now runs a unified government.