The Three GOP Presidential Candidates Who Could Help Their Party Keep the Senate

In a rarity, Republicans are likely to nominate a candidate from a state also hosting a major Senate race next year. That's good news for the GOP.

Marco Rubio's bid to become president leaves Florida Republicans with a daunting challenge, defending his newly vacated Senate seat in a race rightfully considered a toss-up.

But their effort to win the Senate battleground could still benefit from Rubio's presence on the ballot in 2016—or, for that matter, from the presence of fellow Florida Republican Jeb Bush.

If either Rubio or Bush wins the presidential nomination, it would change the electoral calculus in their home state, a familiar presidential battleground that would lean Republican with a favored son atop the ticket. And given how closely Senate races mirror their presidential counterparts, a better showing there would likely trickle down the ballot. In theory, a Senate race Republicans are now scrambling to hold could become eminently winnable with either man leading the charge.

In one of the quirks of this election cycle, Republicans have a trio of major presidential contenders who hail not just from swing states, but states that feature a concurrent crucial Senate race in 2016. Along with Rubio and Bush, Wisconsin Gov. Scott Walker could also significantly change his home state's Senate race, in which Sen. Ron Johnson faces a tough reelection.

Bush, Rubio, and Walker together are generally considered the most likely victors of the Republican primary. And while Republicans will focus on their ability to win 270 electoral votes, GOP strategists are quietly optimistic that—while none of those candidates would guarantee a win for his down-ballot brethren—each would at least ensure a major boost to their party's bid to hold a seat.

"In the worst drubbing in a presidential election in the last 30 years, Walter Mondale still won his home state of Minnesota while losing 49 others," said Phil Musser, a veteran Republican strategist. "So to the degree that Rubio or Walker or Bush is the nominee in the general election, I think that's largely a positive for the nominees for Senate in either state."

The difference Walker, Bush, or Rubio could make in a single Senate race could swing the balance of majority control in 2016. Democrats need a net gain of at least five seats to win back the upper chamber—four if they win the presidency and the Senate's tie-breaking vote. Democratic strategists are confident they can make roughly eight states held by Republican incumbents competitive, while safely defending a pair of states (Nevada and Colorado) held by their own party.

But Wisconsin and Florida are close to must-win for the party to have any serious chance of success. President Obama won both twice, and while Wisconsin isn't an open-seat race like Florida, the first-term incumbent Johnson is seen by both parties as one of the two most vulnerable GOP senators, along with Mark Kirk of Illinois.

If the Democratic presidential nominee were to win another seven-point victory in Wisconsin (Obama's margin there in 2012), Johnson would have a massively uphill fight to avoid defeat. Walker's victory isn't assured in Wisconsin, but he would give the party its best chance there since the last GOP nominee to win, Ronald Reagan in 1984. "We would probably lose without Scott Walker," said one senior Republican strategist familiar with the Senate landscape, who was granted anonymity to speak candidly. "With Scott Walker, obviously we have a shot."

Republicans preparing for these Senate races are as excited about the logistical help the presidential campaigns would provide as anything else. In major battlegrounds, Senate and presidential campaigns work in tandem, and the hope is a presidential candidate on home turf would have special expertise, data, and resources to share with the Senate nominee.

"If Marco Rubio and Jeb Bush are going to have a good operation, the fact is we could tap into that," said one Senate Republican strategist, adding that the prospect of working in Wisconsin with Walker, who has run three hypercompetitive races in the state in the last four years, is especially tantalizing because of the data harvested during each contest.

Senate Republicans are also counting on the presidential candidate's pride to become a benefit. Rubio's and Bush's campaigns will depend on winning Florida, just as Walker's general-election candidacy could hinge on capturing Wisconsin. But just as important, neither man will want to lose his home state, a symbolic defeat that would haunt him afterward.

That guarantees each state will receive a sizable financial commitment from the presidential campaigns, likely all the way through until the end of the race. "Those are states—Florida and Wisconsin—that are going to have the largesse of the national party in them," Musser said.

It's difficult to determine how much of an advantage presidential candidates receive from their old constituents, as most recent major-party nominees have come from uncompetitive general election states. Obama's Illinois was solidly Democratic with or without him on the ticket in 2008 and 2012, just as George W. Bush's Texas was under Republican control in 2000 and 2004. Mitt Romney, John McCain, and John Kerry were each from states decided by nine or more points in their respective elections. In 2000, Al Gore lost Tennessee, a state in the process of turning a deep shade of red at the federal level.

Instances when a nominee came from a state with a major Senate race are similarly rare; Scott Brown faced off against Elizabeth Warren in the 2012 Massachusetts contest with Romney on the ballot, but the Bay State's onetime governor was so unpopular in his liberal former state that he ultimately proved a major drag on the ticket there. If he received a home-state boost, it didn't amount to much—Romney lost by nearly 25 points.

Home states could offer less of a boost than they once did. As political polarization rises, voters are less inclined to give nominees a home-state discount, regardless of their ideology. Walker would be competitive in Wisconsin, but analysts have already begun questioning whether he would win amid an electorate more liberal in presidential elections than the ones he faced in his midterm or recall races.

"I don't think Mitt Romney or Jeb Bush being the nominee would necessarily give the candidates a boost in Florida," said Justin Barasky, spokesman for the Democratic Senatorial Campaign Committee. "Florida is a swing state, Wisconsin is a swing state, and there will be enough money spent on these races that these candidates will rise and fall on their own."

There's also the chance Republicans choose to nominate someone other than Bush, Rubio, or Walker. Just don't expect Republicans in Florida or Wisconsin to hope that they do.