Originally published by the Voice of America (www.voanews.com). Voice of America is funded by the US Federal Government and content it exclusively produces is in the public domain. US Senator in Critical Condition After Surgery, Could Shift Power ----------------------------------------------------------------- Balance ------- http://enews.voanews.com/t?r=279&c=745284&l=1009&ctl=15527EB:A6F02AD83191E16002903C16C2BB7AA69574F7DCC14957C0 If Democrat Tim Johnson is unable to complete his term, balance of power in US Senate could shift back to Republicans Senator Tim Johnson (File) A Democratic member of the U.S. Senate is in critical condition in a Washington hospital after emergency surgery. Hospital officials have not released details about the surgery or the nature of Senator Tim Johnson's illness, but news reports quote medical sources who say he had brain surgery. The Democratic senator from South Dakota was taken to George Washington University Hospital Wednesday night after suffering stroke-like symptoms. His spokeswoman said he had not suffered a stroke or a heart attack. If Johnson is unable to complete his term, the balance of power in the U.S. Senate could shift back to the Republicans, just weeks after Democrats narrowly won control after the November general elections. Democrats now have a 51-49 majority in the Senate. But if Johnson is unable to serve, South Dakota's Republican governor would appoint a replacement until elections in 2008. If the Senate is split 50-50, Republican Vice President Dick Cheney casts the tie-breaking vote. Johnson became disoriented Wednesday during a conference call with reporters. He returned to his office, but still was unwell, and the Capitol Hill physician urged that he be admitted to a hospital for tests. Some information for this report was provided by AP. .