We already know Senate Republicans don't necessarily need Donald Trump to win to maintain their majority. They just need to avoid a blowout loss — or get so many more votes than Trump that they can hang on if their party's nominee bombs.

Right now, Senate Republicans in eight of the 10 of the most competitive races are positioned to do just that. They are polling better than Trump — sometimes way better.

The Post's polling unit pulled together data from polls since mid-August that asked about both presidential and Senate candidates. And The Fix's Philip Bump visualized the data for us:

On average, Senate Republicans are polling 4 percentage points better than Trump. That means that on average, in a race where Clinton and Trump are tied, a Republican Senate candidate leads by four points.

In several races, the GOP Senate candidate leads by a lot more. GOP incumbents John McCain in Arizona, Kelly Ayotte in New Hampshire, Marco Rubio in Florida and Rob Portman in Ohio are polling 8, 11 and even 13 points ahead of Trump. (We noticed this trend in an NBC/Wall Street Journal/Marist poll earlier this week, too. And in August, several battleground state polls indicated the same trend.)

If those numbers hold, these Republicans are positioning themselves to hang on even if Trump loses to Clinton — and a few could hang on even if Trump loses by nearly double digits. That's a pretty big cushion, especially given national polling has tightened over the past few weeks. Trump is now behind Clinton an average 2.4 points, according to RealClearPolitics.

Put another way, Senate Republicans appear to be doing what they need to be doing to distance themselves from Trump enough to hang onto their 54-seat majority. 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 in many of these races, this isn't just a few points. And Republicans are outperforming Trump across the board, even as Democrats do everything they can to try to tie these candidates to the man at the top of the ticket.

In fact, the only GOP Senate candidates who are polling behind Trump right now are Rep. Todd Young in Indiana and Sen. Ron Johnson in Wisconsin, both exceptional cases: Johnson was one of the cycle's most vulnerable Senate incumbents before Trump became the nominee, given how the state tends to lean blue in a presidential year. And Indiana rocketed to the top of our most competitive Senate lists last month (despite being a state Trump is expected to win) after former Democratic governor and senator Evan Bayh — and his $10 million in campaign cash — got in the race.

Democrats are still bullish on their chances to take back the Senate. They effectively need to win four seats; they have a real chance in roughly seven. Also on Monday, the Senate Democratic political committee announced they were spending $4 million to boost their challengers in North Carolina and Missouri, two states that tend to trend red at the federal level but where their Democratic candidates are tied or ahead in polls.

So they still have a shot. We're just seeing more and more evidence that they can't simply count on a Clinton blowout to take back the Senate.

Scott Clement and Emily Guskin contributed to this report.