WASHINGTON — A key question looms for vulnerable Republican senators this election: If Donald Trump loses and loses big, can they still survive?
With 11 weeks until Election Day, Trump's declining standing in the polls has GOP Senate candidates preparing for the worst, and they're maneuvering now to put as big a margin as they can between themselves and the top of the ticket.
Some strategists foresee a historic Trump loss and the need to outrun the presidential nominee by at least five to 10 percentage points in states like Pennsylvania, Ohio, New Hampshire and Florida, if Senate incumbents are to prevail in November. Such margins can be achieved, but it's not easy, and most Republicans say there's a limit to how big Trump can lose without taking down nearly every vulnerable congressional incumbent.
Already, GOP senators in Illinois and Wisconsin are widely considered unlikely to survive in November. Few expect the solidly Republican House to change hands, but losses of as many as 15 or 20 seats are forecast.
Most GOP strategists now view a Trump loss to Democrat Hillary Clinton as a certainty, and their only question is how big.
"I'm more likely to think that it's going to be historic than that it's going to be close," said GOP strategist Rob Jesmer, formerly executive director of the National Republican Senatorial Committee.
Democrats need to pick up four Senate seats to claim the majority if they hang onto the White House, since the vice president breaks tie votes. While Republicans are playing defense in more than a half-dozen heavily contested states, Democrats have only one seat at risk, in Nevada, where Senate Minority Leader Harry Reid is retiring. Instead Democrats are expanding their list of pickup opportunities, adding Indiana by recruiting former Sen. Evan Bayh and working on North Carolina and Missouri.
Republicans take comfort in the fact that for now, incumbents including Sens. Rob Portman of Ohio, Pat Toomey of Pennsylvania and Marco Rubio of Florida are running well-ahead of Trump in their states. Polls show Trump losing all three states, even as Rubio and Portman are ahead of their rivals and Toomey is close to Democrat Katie McGinty.
"Strong Senate candidates can stand on their own even if they are fighting against the tide, and there are numerous examples of where that's happened," said Steven Law, Senate Majority Leader Mitch McConnell's former chief of staff who now works with Super PACs dedicated to helping Republicans.
In 2012, Barack Obama's re-election bid was a drag on Democrats in red states. Nonetheless, Democrat Heidi Heitkamp won in North Dakota even as Obama lost the state by 20 points and Democrat Jon Tester won in Montana even as Obama lost there by 14 points.
In 1996, GOP presidential nominee Bob Dole was headed for such a clear loss that Republicans began to run ads calling on voters to keep them in control of Congress to provide a check on Bill Clinton in the White House. It worked as Republicans won Senate seats that year even while losing the White House. In Arkansas, Clinton won his home state by 17 percentage points but a Republican won the Senate race.
This year, too, Republican senators and strategists are openly discussing split-ticket voting and messages aimed at convincing voters that a Hillary Clinton victory would only increase the imperative for a Republican Congress to act as a check on issues including Supreme Court nominations. Strategists anticipate that a clear pivot to that message could come after Labor Day.
Political committees are paying pollsters to ask voters whether they view their GOP senator as the same as Trump or different, as campaigns focus intently on separating their candidate from the nominee.
Republican senators have been working to focus on local issues and home-state achievements, even as Democrats try to link them to Trump and his controversial statements about women and minorities. With the exceptions of Toomey and Mark Kirk in Illinois, GOP senators up for re-election have mostly said they will support Trump even as they've kept him at arm's length, attempting to at once maintain the backing of his core supporters without alienating independent voters and others.
The top Senate races are awash in money, as donors including the billionaire industrialist Koch brothers have checked out of the presidential race and are focused on saving Senate Republicans instead.
Whether any of it will be enough to preserve Republicans' slim Senate majority remains to be seen.
In Pennsylvania, "I certainly think the senator's going to do well and I think he can outperform Donald Trump," said Mike Barley, a GOP strategist in the state, speaking of Toomey. But "if you're talking about a 10-point-plus (Trump) loss, the path to victory is extremely narrow, if it exists at all."
Toomey is seen as a strong incumbent running a good race, as are Kelly Ayotte in New Hampshire, Portman and Rubio. In Nevada, Republicans are bullish about their nominee for Reid's open seat, Rep. Joe Heck. By contrast some of the Democratic candidates, including Ted Strickland in Ohio, seem to be underperforming expectations. Frustrated Republicans say that if none of that ends up mattering, they'll know who to blame.
Said GOP consultant Brian Walsh: "If Republicans lose the Senate the responsibility for that will lie solely with Donald Trump."
Associated Press writer Marc Levy in Harrisburg, Pennsylvania contributed to this report.