It's a perfect example of the damage Democrats hope to wreak by painting Republicans into a corner with their own sometimes conflicting positions. Gallagher, for instance, denounced Trump's "disgusting and offensive comments" but did not withdraw his support for the GOP nominee.

Fresh internal polls conducted by the DCCC - the House Democrats' campaign arm - after the second presidential debate on Monday (AEDT) painted a grim picture for Republican lawmakers.

They show that Republicans - who started moving en masse against Trump after the revelations in the videotape - faced a backlash regardless of whether they continued to support Trump or not. On Monday, House Speaker Paul Ryan told his colleagues in a conference call that he would no longer campaign for or defend Trump in public, but did not entirely rescind his support for the GOP presidential nominee.

The speaker plans to spend the next month, he told lawmakers on the call, "only campaigning for House seats and not going to promote or defend Trump," according to a GOP lawmaker. Ryan plans to campaign in 17 states and 42 cities in October to help preserve his majority.

Battered: Donald Trump during the second presidential debate. AP

Ryan's decision underscores a significant shift in the GOP's confidence about their ability to retain majorities in both the House and Senate.

Democrats believe that Republicans are now stuck in the impossible position of either embracing their party's presidential nominee and pleasing their base, or rejecting him and alienating swing voters critical to maintaining their hold on Congress.

While a generic ballot tests shows a Democrat up by 7 points over any Republican lawmaker, the DCCC's poll - conducted nationwide by the Global Strategy Group - shows the Democratic candidate has a 12-point edge if the Republican recently withdrew their support from Trump. If a Republican lawmaker continues to support Trump, the private polling shows they are at a similar 12-point deficit.


"The only thing limiting us is our own budget and where opportunities exist in the battle field," Ward said.

Trick for Republicans is to distance themselves from Trump without associating themselves with Hillary Clinton. Bloomberg

The survey showed than 61 per cent of voters said Republicans who decided to withdraw support for Trump over the past few days "lack character and integrity", compared with 39 per cent who said those Republicans "are showing character and integrity for standing up to Donald Trump".

Winning control of the Senate, where Republicans hold a slim four-seat majority, has long been considered a much easier feat for Democrats as there are a number of GOP incumbents in blue states up for re-election. But securing the House majority was always seen as a longshot. As recently as last month, House Democratic leaders speculated that they might win 20 seats, still 10 short of their 30-seat goal.

Upper hand

With the videotape and Trump's decision to highlight Bill Clinton's peccadillos, Democrats think they now have the upper hand with independents, moderates and women in heavily populated suburban districts.

Democrats have their eyes on the 26 Republican House districts that Obama won in 2012 and an additional 23 where he came close to winning. That means taking on Republican incumbents like Barbara Comstock in the suburbs of Washington, DC; Mike Coffman in eastern Denver, Erik Paulsen outside of Minneapolis and Crescent Hardy outside of Las Vegas. All of those Republicans have rejected Trump, many of them in the last couple of days.

But Paulsen's Democratic challenger, Terri Bonoff, said the congressman can't distance himself from Trump at this point.


"It's too late to disavow Donald Trump," said Sean Oyaas, Bonoff's communications director.

Oyaas believes the 2005 videotape is "the straw that broke the camel's back" in a litany of "crude, dangerous things" from the Republican nominee.

Leftward shift

In the final stretch, Republican strategists and leaders have been encouraging members to focus on presenting themselves as a check on a Hillary Clinton presidency that could potentially result in a leftward shift of the country. Members have been told to do everything they can to localise their races and convince voters there is value in electing an experienced, knowledgeable advocate.

"You're walking a tightrope," said Kevin Madden, a partner at Hamilton Place Strategies who previously served as spokesman to then-House Speaker John Boehner. "The candidates that very early on made their congressional race a choice between them and a candidate that was out of step of the district - not a litigation of whether you were for Trump or Clinton - those are going to be the ones that survive."

Republican candidates "have to elevate the fact that they are aligned with the majority of voters on issues they care about", Madden said.

The seemingly impossible choice has many Republican strategists privately preparing for the worst while publicly promising to soldier on.

Others say that they're relying on Trump's history of regaining ground after previous gaffes to help preserve the GOP majority.

"Do I think house Republicans are going to lose seats? Yes," said Thomas Reynolds, a retired GOP congressman from New York and former chairman of the House Republican campaign arm. "Do I think they'll lose the majority? No."