If you are serving the "public," it would be wise to know who the public is. If the statistics are correct, the GLBT community makes up as much as 20% of the population. That's not an insignificant fraction, especially when you consider how many people actually vote.
Many current politicians listen far too much to the radical right, especially the Christian right. They don't make up any more of the population than the GLBTs do. But they are giving you bad, usually misinformed, advice.
If you actively work with the GLBT community and mobilize their vote, you can gain such a substantial voter base that you would be all but guaranteed a win. Add in messages that speak to their friends and family, and you could be making a great investment in the future of your career, not to mention actually serving the public!