Testing the waters
In the United States, the phrase testing the waters is used to describe someone who is exploring the feasibility of becoming a candidate for political office. It can also be used more generally as an idiom meaning to estimate the success of something by trying it out a little bit. "Testing the waters" activities are to be paid for with candidate-permissible funds. Once an individual begins to campaign or decides to become a candidate, funds that were raised or spent to "test the waters" apply to the $5,000 threshold for qualifying as a candidate. This is because there is a federal law that once an individual raises or spends $5,000 for a campaign, they are required to register as a federal candidate.