Outside groups delivering for Marco Rubio

WASHINGTON — It looks like Sen. Marco Rubio’s allies were serious when they assured him he'd get plenty of financial help if he ran for a second term.

In the last few weeks, independent groups have spent more than $3 million boosting Rubio's candidacy and attacking his likely Democratic opponent, Rep. Patrick Murphy.

Murphy’s supporters have countered with more than $1.3 million for the Treasure Coast congressman.

Combined, outside interests have poured nearly $180,000 a day into the Florida Senate race over the past month, an amount that figures to accelerate exponentially after the Aug. 30 primary. State residents can expect a barrage of TV and mailed ads that will last through Election Day on Nov. 8.

Rubio, who initially said he wouldn't run for re-election but later changed his mind, faces his most serious primary challenge from Manatee County developer Carlos Beruff. Murphy’s top rival for the Democratic nomination is Orlando Congressman Alan Grayson.

Super PACs, permitted under a landmark 2010 Supreme Court ruling to spend unlimited amounts of money supporting or opposing individual candidates, have become a major force in politics, especially in presidential campaigns.

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But prominent, wealthy Republican donors who are disenchanted with GOP presidential nominee Donald Trump will spend less on that race and more on downballot races like Florida's Senate contest, analysts say. The Florida race will play a key role in determining control of the chamber.

Billionaire GOP donor Charles Koch has said he’s so disillusioned with Trump that he’ll focus his resources on keeping the Senate in Republican hands. That means Rubio likely will be a major beneficiary of spending by the Koch-affiliated super PAC, Freedom Partners Action Fund.

Daniel A. Smith, a University of Florida political scientist who specializes in campaign finance, said Democratic presidential nominee Hillary Clinton’s surge in the polls is another reason GOP-tilting super PACs likely will be more more active in congressional races.

“Campaign dollars are finite and strategic actors such as the (U.S.) Chamber of Commerce and others and others are not going to waste their money on a candidate who doesn’t have a good shot of winning,” he said, “And right now, Donald Trump’s odds are fairly low, so they’re going to do their mightiest to make sure allies such as Marco Rubio stay in office.”

It’s why the Chamber of Commerce and the Karl Rove-backed Senate Leadership Fund each spent about $1.5 million last month on separate ads attacking Murphy following news reports that he had inflated his work credentials.

“Murphy will have no shortage of financial support from Washington Democrats, and we intend to do what is necessary to prevent them from buying the woefully unaccomplished Murphy a seat in the U.S. Senate,” said Ian Prior, spokesman for the Senate Leadership Fund.

Polls show Rubio leading Beruff in the primary and beating Murphy and Grayson in hypothetical general-election matchups. Rubio said after bowing out of the Republican presidential nomination race in March that he wouldn't run for re-election. But he reversed course after prominent Republicans, including Senate Majority Leader Mitch McConnell, R-Ky., lobbied him to change his mind and said they'd support him.

Murphy already is getting a boost from top Democrats, including President Obama, in his primary battle with Grayson.

The Senate Majority PAC spent $1 million in July on ads showcasing Obama’s support for Murphy. Floridians for a Strong Middle Class, a pro-Murphy super PAC, also spent more than $300,000 on ads in August.

“Marco Rubio and his allies are not telling the truth about Patrick Murphy and we aren’t going to let their attacks go unanswered,” said Shripal Shah, spokesman for Senate Majority PAC said when the group's ad was released.

Smith said it’s hard to know how much the torrent of ads funded by outside groups will sway voters in the general election three months from now. But they could have an impact in the primary, a traditionally low-turnout election.

“The outside money can certainly play a role, especially in those races where the candidates aren’t as well known, where people don’t have firmed-up opinions of them ” he said.