A general rule of American politics these days is that the electorate is so polarized that three-quarters of voters wouldn’t be able to agree on anything at all. But rules, as the saying goes, are made to be broken.

As President Trump's impeachment trial entered its second week on Tuesday, Quinnipiac University released a jaw-dropping new poll showing 75 per cent of registered voters — 49 per cent of Republicans, 95 per cent of Democrats and 75 per cent of independents — believe the Senate should allow witnesses to testify.

The combination of such strong public support for witness testimony and the news that a soon-to-be-released book written by John Bolton — The Room Where It Happened — would contain details of damning conversations between Trump and his mustachioed former aide meant Senate Democrats were standing a bit taller as they walked around the Capitol Tuesday evening.

And when reports emerged from Senate Republicans' weekly caucus meeting which indicated that Majority Leader Mitch McConnell had not locked down the 51 votes it would take to preclude consideration of witness testimony, it appeared as if Democrats were one step closer to their goal of compelling Bolton to testify.

Senators have now begin a two-day period during which they can submit questions which Chief Justice John Roberts will put to the House Democrats' managers and the president's lawyers. Whether they will vote to allow witnesses on Friday is still anybody's guess.

A handful of Republicans, including Maine's Susan Collins and Utah's Mitt Romney, have indicated that they'd like to hear from Bolton. Additionally, the fact that McConnell didn’t lock down a majority vote on Tuesday means that at least two more Republicans, at minimum, are on the fence.

Much of the speculation regarding who else might break with Trump and vote against the majority of the GOP caucus has centered on Senators who will be on the ballot this year in swing states, including Arizona's Martha McSally, Colorado's Cory Gardner, and North Carolina's Thom Tillis.

Larry Sabato, the founder of the University of Virginia's Center for Politics, said it makes political sense for swing-staters like Collins or Gardner to vote for witnesses, particularly since they'll still be able to vote to acquit Trump later on.

"Given the fact that they know they can please and will please Trump in the end [with an acquittal], it gives them some leeway," he told me. "Every day the story changes, but I know if I were in a competitive state, I would want to vote for witnesses. It's a good counter to the claim that they're just hiding the president's missteps."

And while voting to allow witnesses might incur the president's wrath now, Sabato said voters' memories aren't long enough for Friday's vote to matter in November.

"Nobody is going to remember this. It will be in the tenth paragraph of a story and people will say, 'Oh, that's right. That happened at the beginning of the year, didn't it?'"

But Sabato warned that it's highly unlikely even the most damning testimony would cause any currently acquittal-minded Republican to vote to remove Trump, even if the addition of witnesses pushes the trial past some primary filing deadlines: ”I don't think it'll make the slightest difference because they don't want to ever have to say, 'I can't go home again.' And if they do anything contrary to what President Trump wants, with one tweet, Trump can activate his base in their state and their life is miserable and they will be booted out in November."

He added that while it's a tough position for any politician to be in, he isn't sympathetic to their plight.

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"They are stuck and they have no one to blame but themselves because they have completely and totally handed Trump the keys to their conscience," he said. "I have no sympathy for them whatsoever."

But some observers think those who are watching to see if swing-state Senators will join Democrats are looking in the wrong place. Instead, the biggest bloc of votes for witnesses could come from so-called “institutionalists" — veteran GOP stalwarts like retiring Tennesee Senator Lamar Alexander, Pennsylvania's Pat Toomey, or North Carolina's Richard Burr, who chairs the Senate Intelligence Committee.

"It's not a good place for the White House to be in," one top Republican operative told me. What the White House fears most, he said, is Senate veterans like Burr — or even Alabama's Richard Shelby — joining Collins and Romney in voting to allow witnesses, which could trigger a "jailbreak" by bringing more Republicans along with them.

"If you get Burr, Tillis flips," a longtime Republican Senate watcher predicted, adding that the worst-case scenario for the White House involves eight to 12 GOP Senators joining Chuck Schumer's 47 Democrats.

But one Trumpworld veteran, political consultant Sam Nunberg, said to me that all the handwringing over Friday's vote will come to naught.

"I don’t think there will be witnesses," he said in a text message. "What's the point? The result will be the same."

All the president's lawyers: The team fighting Trump's impeachment Show all 6 1 /6 All the president's lawyers: The team fighting Trump's impeachment All the president's lawyers: The team fighting Trump's impeachment Alan Dershowitz Dershowitz is a controversial American lawyer best known for the high-profile clients he has successfully defended. Those clients have included OJ Simpson, Jeffrey Epstein and Harvey Weinstein. One longtime Harvard Law associated told the New Yorker Dershowitz "revels in taking positions that ultimately are not just controversial but pretty close to indefensible." Getty All the president's lawyers: The team fighting Trump's impeachment Ken Starr Starr became a household name in the 1990s as the independent counsel who led the investigation that led to Bill Clinton's impeachment. That investigation began as a look into a real estate scandal known as Whitewater, and eventually led to impeachment after Mr Clinton lied under oath about having an affair with White House intern Monica Lewinsky. AP All the president's lawyers: The team fighting Trump's impeachment Jay Sekulow Sekulow is the president's longtime personal attorney, and, now, personal lawyer in the White House. He has been accused by former Rudy Giuliani associate Lev Parnas of being "in the loop" during the Ukraine scandal. Getty All the president's lawyers: The team fighting Trump's impeachment Pam Bondi Bondi is the former attorney general in Florida, and a longtime backer of the president's. She made a name for herself in Florida for taking hyper partisan stances on issues, and her penchant for publicity. She is likely to be a prominent public-facing figure during the trial. AFP/Getty All the president's lawyers: The team fighting Trump's impeachment Pat Cipollone Cipollone is the White House counsel, and leading the president's defence team. Getty All the president's lawyers: The team fighting Trump's impeachment Rudy Giuliani While not officially named as one of the president's impeachment lawyers, it is hard to ignore Giuliani's outsized role in this process. The former mayor of New York has been making headlines for months as he defends his client, and for his apparent role in the effort to compel Ukraine to launch the investigation into Joe Biden. We'll see how he figures in the actual trial, which he has said he would like to be a part of. Reuters

According to Nunberg, the idea that vulnerable incumbents can gain a veneer of independence from Trump by voting for witnesses but still voting for acquittal is nonsensical.

"It won’t help them with any of their critics once they acquit Trump," he explained.

And while a Senator whose vote remains firmly in Trump's column is McConnell, one Kentucky Republican graybeard I spoke with said the biggest wild-card in all of this is whether he will continue the whip operation he employed to great success last Tuesday, when the Senate voted to approve his trial rules package.