James R. Gorrie, Stock Trader Daily

With the re-election of the president, ObamaCare is a done deal. It's going to happen. Many investors worry that some health care companies will see falling profits, while others will directly benefit from the sea change in American health care. Finding the smartest long-term play in the health care industry can be a challenge, to say the least.

The probability is that no healthcare sector will remain untouched by the health care act. The great fear is that profits will be capped so much as to drive health care companies out of business.

Will this happen? Probably yes, to some extent.

The other side of that coin is that it is politically impossible to drive too many health care companies out of the market. Untreated senior citizens don't win elections. That said, is there a niche in the health care sector that looks more likely to thrive than others over the long term?

If you're a value or income investor who seeks steady growth with rational dividend income, you know that uncertainty clouds your investment horizon. But believe it or not, there are still some certainties that you can bank on, even in changing times.

Actually, there are two certainties.

One is demographics. In a nutshell, Americans are getting older. This is because the leading edge of the baby boomer generation turned 65 in 2011. Every year for the next two decades, tens of millions of Americans will become senior citizens. If there's one constant about older people it's that they need more health care, a lot more.

The second certainty is the advancement of medical science. Today, people are living longer than ever. The life expectancy of the baby boomers is over 80 years for both men and women, and medical advances now provide more human replacement parts and fantastically engineered, life-extending drugs than ever before.

Combine both of those certainties and you have an enormous and virtually untouched market with rising demand from the baby boomer generation, with a long tail of medical-related revenues into the future. That means tremendous upside for health care companies positioned to capture that market.

Which health care niche best leverages these two certainties and provides income? The obvious answer would be the healthcare REITs. They not only capture those markets, but also must pay out 90% of taxable income as dividends, in some cases even in bankruptcy.

But which healthcare REIT looks like a winner?

Many look attractive in the long run, such as Health Care REIT (HCN), Omega Health Care Investors (OHI), Senior Housing Properties Trust (SNH). But HCP (HCP) is the largest in its class and the only one that operates life science centers. HCP is also well positioned not only in medical offices and assisted living facilities, and is a dominant player in Ohio, Michigan and Florida, three of the country's largest retirement markets. Its market capitalization is about $14 billion, and it pays as dividend 4.5%.

Find here more great research on healthcare REITs.