The rise of the Tea Party insurgency in 2009 and 2010 came with an oft-overlooked benefit for the Republican Party and conservative movement. Not only did the insurgency provide energy to the anti-Obama wave in the 2010 midterms, but it helped blur the lines between the parties in a way that was deeply beneficial to Republicans in a time of deep anti-Wall Street sentiment in the electorate. Backed by the upsurge in Tea Party populism, the party of Mitt Romney and Phil Gramm was remarkably able to cast itself as the party of Main Street against those banker-bailing, crony-capitalist Obama Democrats. Never mind that candidates under the Tea Party banner were being fueled by the financier-backed Club for Growth, that Scott Brown was powered more by a surge in financial industry contributions than Tea Party backing in his upset victory for Ted Kennedy's seat, that Wall Street spending in 2010 swung sharply behind the GOP—all that mattered was embracing that nebulous Tea Party aura.

It was hard to sustain this opportunistic blurring of the lines over time. In 2011, the Tea Party contingent in the House of Representatives was championed by none other than Eric Cantor, the leading recipient of Wall Street campaign contributions in the House and the staunchest defender of the carried-interest-loophole for private equity partners and hedge fund managers, not exactly a populist cause. (So disingenuous was Cantor’s claim to being an insurgent advocate that he was upset by a conservative primary challenger in June.) In 2012, the party nominated for president someone who rhapsodized to high-dollar donors about the laziness of the poorest 47 percent of Americans.

Now, the game may finally be up for good. Republican candidates are still doing their best to co-opt lingering Tea Party fervor, even as the party has done its best to quash conservative primary challengers in Senate races in Kentucky, Mississippi, and elsewhere. But the lines of allegiance are clearer than ever. First came reports earlier this month that Wall Street was spending heavily on behalf of Republican Senate candidates with the very specific aim of keeping Sherrod Brown, the gravel-voiced Ohio Democrat, from assuming the chairmanship of the Senate Banking Committee, as he might just do if the Democrats retain the majority. In past elections, The Washington Post reported, "securities and investment firms have hedged their bets by donating roughly the same amount to both parties. But this time Wall Street has handed Republicans nearly two-thirds of the $115 million it has contributed to 2014 campaigns..."

Wall Street’s heavy investment to keep Brown from taking the gavel is striking given that Brown is not exactly William Jennings Bryan or Huey Long, notes Dennis Kelleher, a former senior leadership advisor to the chairman of the Senate Democratic Policy Committee who now runs a pro-financial reform organization, Better Markets.* But even though Brown is not a firebreathing populist, he’s considered unacceptable by the banks. “Wall Street doesn’t like anybody who doesn’t agree with them almost all of the time, or someone who is smart enough and stand-alone to question them,” says Kelleher. “If you’re not viewed as one of the boys who’s going to go along with them, they’re not going to like you.” And the money to stop Brown and the anonymous pot shots against him are coming from a specific sector of the financial industry, notes Kelleher. “When you see complaints, it’s almost always coming from the handful of too-big-to-fail banks,” he said. “The big regional banks, the community banks aren’t criticizing Sherrod Brown… When you get to the core people who are complaining, it’s the handful of too-big-to-fail banks.”

The irony, adds Kelleher, is that breaking up these banks, as Brown and others suggest, would make the country’s financial system more robust. “If instead of having a bank with $2.5 trillion under management, you have three banks with $800 billion, is the country really worse off? You’d have greater competition and greater diversity of products,” he said. “Even if it stayed a $2.5 trillion bank and was regulated in such a way that the bank is not a threat to the country, the country would be better off. But the bank executives and their bonuses would not be better off, and that’s why you have the anonymous vilification of Sherrod Brown.”

And it’s not just the banks who are making preferences clear with their campaign giving. The U.S. Chamber of Commerce is more tilted toward Republicans than ever, with only five Democrats among its 280 endorsements. (If one needs any further proof of the corporate absorption of the Tea Party, consider that the Chamber is running ads against Kay Hagan in North Carolina that feature Rand Paul, the great Tea Party hero of 2010.) Business PACs have also pushed their giving toward Republicans in close Senate races this year, the Wall Street Journal reported this week: "Political-action committees created by businesses had given 61% of their donations in those races to Democrats this election cycle through June. That reversed in the closing months of the campaign, with only 42% going to Democrats and 58% to Republicans in the July-to-September quarter..."

The biggest contrast in corporate giving came in the Kentucky Senate race, where Mitch McConnell has received more than $3 million from business PACs while his Democratic challenger Alison Lundergan Grimes has received a grand total of $20,760—that is, less than one percent than McConnell. No doubt, some of that differential reflects the calculation by corporations that McConnell is likely to win and become Senate majority leader, and that it is better to be in his good graces.

Still, the swarm of business PAC cash for McConnell makes further mockery of his own attempts to co-opt the Tea Party populism that swept his fellow Kentuckian, Paul, into the Senate in 2010, over McConnell's preferred establishment candidate. McConnell hired Paul’s campaign manager (the husband of Paul’s niece) to run his own campaign as a way to keep as many as possible of Paul’s Tea Party supporters in the fold during the GOP primary, and he laced his campaign rhetoric with fiery populist appeals that were a long way indeed from the sobriety of the young Republican who was such a firm believer in moderation that he opposed Ronald Reagan in both the 1976 and 1980 Republican presidential primaries.

The ruse worked well enough to give McConnell an easy win against his Tea Party challenger, but that’s about it. If he and his fellow Republicans claim the Senate majority next week, there’ll be little doubt about the forces that got them there—more JP Morgan Chase than Tom Watson. The 2014 midterms may not have been particularly nourishing, but they have been clarifying.

*This piece was updated on Thursday night. The piece initially referred incorrectly to Kelleher as a former aide to Senate Majority Leader Harry Reid.