Nothing Is Stopping You, Mr. Gruener
But as it happens, if Gruener really is serious about wanting to pay more to the U.S. federal government, he can do so right away, regardless of how the future political battle over the possible extention of the Bush tax cut ends. Just go to the website of the Bureau of Public Debt and follow the instructions on how to pay more money to the U.S. federal government. If he is really serious about wanting to give more money to the government he can set an example by doing so right away.
And so can by the way any other American reader who for some reason feels that it would be good if they paid more money to their federal government. Note however that while I do inform you of the possibility I do not recommend it and I would not view that as rational. If you can spare some money and want to give it away to others who deserve it, there is at least one person a lot more deserving than the U.S. federal government.