Senate Republicans don't necessarily need Donald Trump to win for them to hold onto their majority. (In fact, some of them are campaigning on a Trump loss.) They just need him to avoid a blowout loss.

And on Monday, as the presidential race tightens, we have even more evidence that even if Trump loses to Hillary Clinton by roughly 3 to 5 points, Senate Republicans could hang on. The Fix's Philip Bump pulled the latest polling averages from RealClearPolitics and found that of the 13 most competitive Senate races this cycle, Republicans are outperforming Trump in nine. Sometimes by a lot.

  • In Ohio, Sen. Rob Portman (R-Ohio) is polling better than Trump by more than 13 points.
  • In Arizona, Sen. John McCain (R-Ariz.) is polling better than Trump by 9 points.
  • In Illinois, one of the Senate's most vulnerable GOP incumbents, Sen. Mark Kirk (R), is down by 7 points, but Trump is down by almost 15 points, meaning Kirk is outperforming Trump by nearly 8.
  • There's even some good news for Republicans in the hotly contested Pennsylvania Senate race, where Sen. Patrick J. Toomey (R) is trailing Democrat Katie McGinty by 2 points: At least Toomey isn't down 5.6 points, like Trump is.

One of the most impressive performances by a Senate Republican comes in one of the Senate's biggest battles. Even though Clinton is up by more than 5 points over Trump in New Hampshire, Sen. Kelly Ayotte (R) is leading her Democratic challenger by 2.7 points. That means Ayotte is outperforming her party's nominee by almost 8 points — and this is after twisting herself into a virtually unrecognizable pretzel to kind of sort of support Trump.

It isn't all that unusual for an incumbent senator to be polling ahead of their party's presidential nominee by a few points. But to be ahead of the nominee by 8 or 13 points is almost unheard of in modern-day politics. Modern-day voters have been abandoning the practice of split-ticket voting, where they might mark the ballot for Democrat for president then vote for the Republican for Senate.

In 2012, almost no Republican Senate candidate outperformed Mitt Romney. (The outlier was Sen. Dean Heller (R-Nev.), who outperformed Romney by almost 8 points.) In that election, only 4 percent of voters voted for both Barack Obama and a Republican congressional candidate.

But Senate Republicans are consistently defying the odds this election cycle. In mid-September, we found that on average, Senate Republicans were polling 4 percentage points better than Trump. A month and a half later, they're outperforming Trump by an average 3.3 points.

It's also helpful for Senate Republicans that the presidential race is tightening: Clinton is ahead by just 2.5 points, according to a RealClearPolitics average.

Speaking of Ayotte and pretzel-twisting, the reason Senate Republicans are hanging on likely comes down to this: They're doing what they need to do to distance themselves from Trump. Almost all of the Republicans on this list have distanced themselves from Trump in one way or another; several ditched Trump right after The Tape, and a handful are campaigning as if Clinton is already president, promising to be a “check and balance” on her.

The four outliers, where Trump is outperforming his party's Senate candidate (Missouri, Indiana, Wisconsin and Colorado) can mostly be explained by struggling Senate Republican candidates. Most political observers already have Wisconsin and Colorado in Democrats' column; Indiana is a toss-up thanks to a strong Democratic challenger in former senator Evan Bayh.

Missouri is likely the most troubling for Senate Republicans. Sen. Roy Blunt (R) was not expecting a strong race, and yet Trump is outperforming him by more than 6 points.

To be clear, Democrats are still the favored party to take back the Senate. They effectively need to win just four seats; they have a real chance in five to seven. And just because a candidate like Kirk is outperforming Trump doesn't mean he'll win — Kirk is still down by an average 7 points, after all.

Democrats may still be poised to retake the Senate majority. But Republicans aren't making it easy.