Donald Trump may be down in the polls, but Republican Senate candidates are still faring relatively well, suggesting — at least for now — that they may escape being drawn down by the whirlpool that analysts predicted would drown all who surround the billionaire businessman.
While presumptive Democratic presidential nominee Hillary Clinton tops Mr. Trump in matchups in Florida, Pennsylvania and New Hampshire, incumbent Senate Republicans are all ahead in polling in their own races, building significant leads.
“We’re seeing in numerous states and districts at the moment very substantial levels of potential ticket-splitting,” said Whit Ayres, a Republican pollster.
Sen. Marco Rubio, who recently reversed course and said he would seek re-election in Florida, was leading two potential opponents by 7 or 8 percentage points in a Quinnipiac University poll last month — even as Mrs. Clinton held an 8-point lead over Mr. Trump in that state.
In Pennsylvania, Sen. Patrick J. Toomey held a 9-point lead over Democrat Katie McGinty, while Mr. Trump trailed by 1 point in a recent Quinnipiac survey. In New Hampshire, Sen. Kelly Ayotte led by 9 points over her Democratic challenger, Gov. Maggie Hassan, in a recent American Research Group poll, while Mrs. Clinton was up 5 points in the presidential race.
Mr. Rubio, Mr. Toomey and Ms. Ayotte are all first-term senators, elected in the 2010 tea party wave, and their seats have been seen as critical pickups for Democrats to have a hope of taking control of the Senate.
Republican leaders, even as they try to find ways to back Mr. Trump, are hoping voters don’t punish the rest of the party for nominating him.
“I think the Senate races are going to be big enough to where they’re largely unaffected by the top of the ticket,” Senate Majority Leader Mitch McConnell, Kentucky Republican, said in a recent interview with The Associated Press. “I don’t think we’re going to have a wave election this year in any event.”
Mr. Ayres said tickets haven’t been split much in recent elections because down-ballot candidates have tended to align themselves closely with their parties’ presidential nominees. That is not the case this year, and voters are being asked to split their tickets.
“People are perfectly capable of splitting their tickets, and it looks like if the parties follow through with their presumptive nominees, then this year we could have a record level,” Mr. Ayres said.
A number of groups are aiming to help Republican senators. The U.S. Chamber of Commerce, which is feuding with Mr. Trump over trade policies, is committing to massive spending in Senate races.
Meanwhile the Senate Leadership Fund, an independent political action committee run by Mr. McConnell’s former chief of staff, recently announced close to $40 million in ad reservations to boost Republican Senate candidates in New Hampshire, Ohio, Nevada, Pennsylvania and Missouri. The group said it will make buys in additional states in the coming weeks, including in Florida.
Prominent Republicans, such as 2012 presidential nominee Mitt Romney, and Ohio Gov. John Kasich, who are also feuding with Mr. Trump, have signaled they will campaign for down-ticket candidates in their party.
Republicans hold an effective 54-46 majority in the Senate but are defending more than twice as many Senate seats as Democrats, again because of their overwhelming victory in the tea party wave six years ago.
Democrats have eagerly tried to tie down-ticket candidates to Mr. Trump, arguing that they share the same policies on immigration and other hot-button issues. Despite some notable exceptions, voters generally default to party-line voting.
In the 2012 elections, the winners of just 26 U.S. House races were from a different party than the district’s choice for president, according to data compiled by Bloomberg.
Aside from Sens. Bernard Sanders and Angus King, two independents who caucus with Democrats, just 16 senators hold seats in states that their party’s presidential candidate lost in 2012. Of those 16, seven are Republicans up for re-election this year.
“What history tells us is that voters don’t tend to make that much of a distinction between the candidates, and party is more powerful than [an] individual candidate,” said Jeff Horwitt, senior vice president at Hart Research, a polling firm whose clients include a host of House and Senate Democrats.
Republican Party strategist David Winston said part of the reason voters are splitting tickets less frequently is an increasingly negative tone in campaigning.
“It’s not identifying why you should vote for somebody but why the other person’s wrong, and that tends to reinforce partisanship,” he said. “When you focus on the negative, it tends to reinforce the partisan views.”
He said that creates an opening for Republican senators such as Mr. Rubio, Ms. Ayotte, Ron Johnson in Wisconsin and Rob Portman in Ohio to distinguish themselves. They can argue that they are known commodities and can legitimately break with Mr. Trump when warranted, he said.
“The dynamic there is you representing your state and if there’s disagreement, you’re going to represent your state,” Mr. Winston said.
Ms. Ayotte and Mr. Johnson, for example, have been careful to try to make a distinction between voting for Mr. Trump or supporting him and “endorsing” his candidacy.
Mr. Horwitt, though, said that distinction is likely lost on voters.
“I understand that there are individual races and sometimes there are candidates in races that have their own profile and are able to overcome that, but generally speaking, even with Trump’s unique candidacy, I think you do start to see people fall into line,” he said.
Another set of battleground state polls conducted by Greenberg Quinlan Rosner Research provided more of a mixed picture — but nowhere close to the down-ballot electoral wipeout Democrats and some Republicans have been forecasting for Mr. Trump.
The Republican Senate candidates in Pennsylvania, Wisconsin and Nevada were all running ahead of Mr. Trump in those surveys. The Senate races in Ohio, New Hampshire and Arizona, meanwhile, were all within the margins of error, though the Republican candidate was leading by 2 points in Arizona, trailing by 1 point in New Hampshire and trailing by 3 points in Ohio.