The Constitution of the US is the supreme Law of the Land (Article VI) and Amendment 15 states that the right of citizens of the United States to vote shall not be denied.
US Senators take an oath to support and defend the US Constitution. Any act performed by a US Senator to keep another US Senator from voting is in violation of the US Constitution and must be stopped immediately.
Although the act of filibustering has been a tolerated behavior, it is also against the supreme Law of the Land. Allowing any act by a US Senator that denies another citizen of the US the right to vote is stating that US Senators are above the law and that is drastically against the foundation of the United States of America.
Additional Information: http://my.barackobama.com/page/community/blog/davidbiagini