A slim majority of the midterm congressional campaign contributions from America's biggest companies have gone to Republican candidates, an Axios analysis of federal election data shows.

Why it matters: America's wealthy companies are able to influence elections by financially supporting candidates whose positions align with their values — or who they believe can help their businesses. But even more often, they support both sides, ensuring access to whomever ends up in power.

The chart above shows 495 of the 500 largest U.S. companies by revenue. Five were missing from the OpenSecrets database, which Axios used for this analysis.

The companies' size is based on the combined contributions from their political action committees and individual employees who gave at least $200.

is based on the combined contributions from their political action committees and individual employees who gave at least $200. They are grouped from top to bottom according to their economic sector. Sectors that gave a larger share of their contributions to Republicans are on top, while sectors that preferred Democrats are towards the bottom.

By the numbers: Employees and PACs affiliated with Fortune 500 companies have given more than $180 million to congressional candidates in the 2017–2018 campaign cycle.

Republican candidates received nearly $93 million, or 52% of the Fortune 500's spending. About $86 million, or 48%, went to Democrats.

received nearly $93 million, or 52% of the Fortune 500's spending. About $86 million, or 48%, went to Democrats. The energy sector , which includes fossil fuel companies like Exxon Mobil and Chevron, gave more than four-fifths of its $8.5 million in contributions to Republicans.

, which includes fossil fuel companies like Exxon Mobil and Chevron, gave more than four-fifths of its $8.5 million in contributions to Republicans. But the technology sector gave about three-quarters of its $17.7 million to Democrats. The largest overall contributor, Google's parent Alphabet, gave about 86% of its $4.7 million to Democrats.

The bottom line: “Certain industries lean right or left, but major corporations generally hedge their bets—favoring the party in power, but delivering hefty sums to both sides—and on that score, 2018 is no different,” said Sheila Krumholz, executive director of the Center for Responsive Politics, the watchdog group that maintains OpenSecrets.

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