In case you haven't heard, Texas Gov. Rick Perry, who quickly has become a leading contender for the Republican nomination for president, is making climate change a campaign issue, saying scientists have manipulated data to support "unproven" theories that humans are contributing to global warming.

Last week in New Hampshire, Perry made climate change a key element of every speech, according to The Washington Post. Rep. Michele Bachmann (R-Minn.), also seeking the nomination, is very skeptical about climate change.

Candidate Mitt Romney, on the other hand, was criticized by conservatives when he said in June that he accepts the scientific view that the planet is getting warmer, the Post says. Utah Governor Jim Huntsman also says he trusts scientists on global warming.

Generating jobs is likely to be the biggest issue in the Republican primary as well as the presidential race, but climate change could end up being an issue on which candidates take a clear-cut stance that's easy to differentiate and might have some impact on voters trying to make a decision. If the candidate who ultimately becomes president doesn't believe humans contribute to global warming, government policy support for efforts to slow climate change will disappear. While some would cheer that development, many sustainable investors will surely be disappointed.