As Republicans look to defend their newfound Senate majority in 2016, early television and digital spending has more than quadrupled from this same point last cycle, a CQ Roll Call analysis shows.

More than a year out from Election Day 2016, Republican incumbents and GOP-aligned outside groups have shelled out at least $13.3 million to boost their re-election prospects and attack potential Democratic challengers in Senate contests across the map. That’s seven times more than the $1.9 million Republicans spent by this point last cycle — when the GOP was looking to win the Senate majority for the first time since 2006.

Republicans are defending 24 seats this time around, nine in states that President Barack Obama carried at least once. If they lose five — or four if Democrats win the White House — the Senate majority will slip from their grip. Drawing a comparison between this cycle and the last presidential election doesn’t paint an accurate picture because super PAC spending was still in its infancy in 2012.

By this point in the 2014 cycle, when Democrats were defending the lion’s share of Senate seats, GOP spending totaled around $1.9 million, according to a source who tracked ad buys. A majority of the spending — roughly $1.1 million — was in Arkansas, where now-former Sen. Mark Pryor faced the most daunting path to re-election. Pryor ultimately lost to now-Sen. Tom Cotton by a stunning 17-point margin.

Another large chunk — roughly $700,000 — was spent in Kentucky, where now-Senate Majority leader Mitch McConnell faced a primary and general election opponent. And a smaller share — about $80,000 — was spent in Louisiana, where now-former Sen. Mary L. Landrieu faced re-election as a Democrat in a deep red state. Landrieu lost by nearly 12 points.

National Republican Senatorial Committee Chairman Roger Wicker, R-Miss., brushed off the notion that early spending is a sign Republicans are worried about holding the majority.

“What a ridiculous question! We’re doing great!” Wicker told CQ Roll Call in July. “I would think it would be more of an indication that we’re trying to take care of business and be strategic.”

But Democrats say early spending to try and improve incumbents’ favorability among voters is a sign Republicans are worried about next year.

“Ask me any year, if you’re spending money on TV in July on the off year, you’re not doing it from a place of happiness,” said Ben Ray, a Democratic strategist who has worked on a number of Senate campaigns.

GOP groups say early spending is a way to build support for their candidates before campaigning ramps up next year.

“Helping to shape the environment early is a lesson learned from 2012 that we applied, along with many others, effectively in 2014,” said Rob Engstrom, national political director of the U.S. Chamber of Commerce, which has so far spent nearly $2.7 million in six Senate contests across the country. “It’s no longer Election Day, it’s election year.”

Of the millions the Chamber has spent, almost all of it has gone toward positive advertising on GOP incumbents or candidates including Sens. Mark S. Kirk of Illinois, Patrick J. Toomey of Pennsylvania, Kelly Ayotte of New Hampshire and John McCain of Arizona. Kirk, Toomey and Ayotte all face re-election in states Obama won twice.

Only one expenditure — $525,000 — has gone toward a negative spot. That ad attacks former Ohio Gov. Ted Strickland, the likely Democratic nominee to take on GOP Sen. Rob Portman in the Buckeye State — a swing state that Democrats carried in both 2008 and 2012.

Outside groups like the Chamber account for the vast majority of the more than $13 million spent so far.

That figure was calculated by searching the Federal Election Commission’s independent expenditure public disclosures, as well as from a source tracking media buys across the country. Not all of the data is publicly available, as issue-based ads that ask voters to call their senator and encourage them to support or oppose policy is not considered political spending outside of a 60-day window before a general election and 30 days before a primary, and is therefore not required to be reported to the FEC. That spending is only traceable by those with access to ad tracking information from television stations.

For example in Ohio and Colorado, a group is spending millions on air to tout a pro-Republican record, according to The Associated Press — something that could help incumbents like Portman, who will benefit from strong GOP turnout in Ohio.

But GOP senators are also spending money from their own campaign accounts on television and digital advertising to increase their re-election chances.

In Illinois, Kirk spent more than $300,000 on a minute-long bio ad in May, touting his recovery from a debilitating stroke in 2012. Kirk is arguably the most vulnerable Senator up for re-election this cycle, facing voters in a strong Democratic state that Obama twice carried by double-digit margins. His race is rated Tilts Democratic by the Rothenberg & Gonzales Political Report/Roll Call — the only Senate contest so far predicted to flip party control.

In Pennsylvania, Toomey’s campaign has spent five figures to run ads highlighting the work Toomey is doing in the Senate they say benefits his constituents back home.

Toomey faces re-election in a state Democrats have carried at the presidential level every year since 1992, meaning he will likely have to convince many Democratic voters to split their ticket to vote for him.

“There is an epidemic of child abuse and assault in schools, and Senator Toomey is determined to stop it. The two spots that have aired served to inform Pennsylvanians about Senator Toomey’s ongoing and successful efforts in the senate to better protect children from sexual and violent predators while enlisting their support of this important cause,” said Steve Kelly, Toomey’s campaign spokesman.

And in Ohio, Portman has spent six-figure sums on digital advertising to bolster his re-election bid.

“The online effort is part of our data-driven campaign to reach voters both online and through our grassroots programs,” said Corry Bliss, a spokesman for Portman’s campaign.

Matthew Fleming contributed to this report

Related:

Roll Call Race Ratings Map: Ratings for Every House and Senate Race in 2016

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