Who is Gallup?

I think Gallup is the most widely used poll company, here's their bio from Wikipedia:

The Gallup Organization, known primarily as Gallup, provides a variety of management consulting, human resources and statistical research services. It has over 40 offices in 27 countries. World headquarters are in Washington, D.C. Operational headquarters are in Omaha, Nebraska. Its current Chairman and CEO is Jim Clifton.

Gallup currently has four divisions: Gallup Poll, Gallup Consulting, Gallup University, and Gallup Press.

The Gallup Poll
The Gallup Poll is the division of Gallup that regularly conducts public opinion polls in more than 140 countries around the world. Gallup Polls are often referenced in the mass media as a reliable and objective measure of public opinion. Gallup Poll results, analyses, and videos are published daily on Gallup.com in the form of data-driven news.

Historically, the Gallup Poll has measured and tracked the public's attitudes concerning virtually every political, social, and economic issue of the day, including highly sensitive or controversial subjects. In 2005, Gallup began its World Poll, which continually surveys citizens in more than 140 countries, representing 95% of the world's adult population. General and regional-specific questions, developed in collaboration with the world's leading behavioral economists, are organized into powerful indexes and topic areas that correlate with real-world outcomes.

Gallup Polls are best known for their accuracy in predicting the outcome of United States presidential elections. A notable exception is the 1948 Thomas Dewey-Harry S. Truman election, where nearly all pollsters predicted a Dewey victory. This is largely attributed to the polling methods and technology available at the time in comparison to today. The Gallup Poll also inaccurately projected a slim victory by Gerald Ford in 1976, where he lost to Jimmy Carter by a small margin.

For the 2008 U.S. presidential election, Gallup was rated 17th out of 23 polling organizations in terms of the precision of its pre-election polls relative to the final results.

In 2008, Gallup interviewed no fewer than 1,000 U.S. adults each day, providing the most watched daily tracking poll of the race between John McCain and Barack Obama. Gallup publishes the results of its tracking survey in a three-day rolling average on Gallup.com.

Gallup conducts 1,000 interviews every day 350 days out of the year, among both landline and cell phones across the U.S. for its health and well-being survey.