Source: Architect of the Capitol Flickr.

The votes cast and counted, it appears that private Medicaid insurers including Centene (NYSE:CNC), WellPoint (NYSE:ANTM), WellCare (NYSE:WCG) and UnitedHealth Group (NYSE:UNH) were among the losers.

That's because those companies run Medicaid programs in hotly contested states that have yet to adopt Medicaid expansion. If votes had shaken out differently, each would have stood to benefit from revenue growth tied to rising Medicaid enrollment. So, let's look more closely at the missed opportunity.

Biggest in play
One of the tightest contests this election year was for the governorship in Florida, where incumbent Rick Scott faced off against Charlie Crist.

Scott has moved slowly to embrace Medicaid expansion, but challenger Crist would have likely backed it. While on the campaign trail, Crist estimated that expansion could enroll hundreds of thousands of uninsured people in Florida, generating $51 billion in federal funding and creating tens of thousands of jobs along the way.

However, those arguments failed to win enough votes to give him the victory over Scott, and that puts Florida's expansion plans back at square one, which is bad news for Centene and WellCare, two of the state's biggest Medicaid insurers.

According to reports, if Florida chose to expand Medicaid, as many as 1.3 million more people would be covered by private Medicaid insurers. That would mean hundreds of millions of dollars in revenue for Centene and WellCare, which already provide services for 411,200 and 681,000 Floridians, respectively.

Source: Centene.

Smaller markets, but similar outcomes
The tussle for Tallahassee wasn't the only battle lost by Medicaid insurers on Tuesday. A number of other states had close races, too.

Behind Florida, Georgia was the second biggest state in terms of potential Medicaid expansion membership that had a tight race for governor. In that state, incumbent Nathan Deal ended up defeating challenger Jason Carter, in the process denting the likelihood that Medicaid expansion would add 650,000 Georgians to Medicaid plans run by WellCare, which already serves 617,000 members there, and WellPoint, which also does business in Georgia through its Amerigroup subsidiary.

Medicaid insurers were likely watching Kansas, too. Expanding Medicaid in Kansas would have meant an additional 100,000 new members, but challenger Paul Davis failed to unseat Sam Brownback, suggesting that Medicaid expansion is less likely. If that's true, then Centene, which is one of the biggest players in Kansas, with 144,000 members, WellPoint, and UnitedHealth Group will all miss out.

If incumbent Scott Walker had been voted out of office, Wisconsin may have also considered Medicaid expansion as well. Walker shunned federal Medicaid money and reworked Medicaid eligibility during his last term, but his challenger, Mary Burke, would likely have lobbied to embrace it. If so, it would have benefited Centene, WellPoint, and Molina Healthcare, all of which help run Wisconsin's Medicaid program.

Looking ahead
Medicaid expansion has been a big win for insurers in 2014 thanks to more than 8 million people enrolling in the government program in the past year. That's translating into significant revenue growth for insurers.

For example, Medicaid enrollment at Centene grew from 1.95 million a year ago to 2.58 million in the third quarter, helping sales jump 53% to $4.2 billion. And Medicaid membership grew by 28% at WellCare, which helped lift WellCare's overall sales by 35% to $3.3 billion.

Revenue momentum for Medicaid insurers should continue next year, regardless of whether or not these states ever choose to sign onto expansion. That's because Medicaid enrollment is expected to grow by another 13% this year. If that forecast proves correct, these Medicaid insurance stocks will remain strong performers again in 2015.