High court divided over political donor limits October 8, 2013 -- Updated 1612 GMT (0012 HKT) A spirited hour of oral arguments left in doubt how the court might rule The suit challenges the law limiting how much a donor can give to candidates for federal offices The suit does not challenge the limit of $2,600 per candidate Washington (CNN) -- A free-speech legal fight over the fuel of partisan politics -- the billions at stake in federal campaign donations -- produced a predictably divided Supreme Court on Tuesday. A spirited hour of oral arguments left in doubt whether current aggregate limits on direct campaign contributions by individuals -- in the Federal Election Campaign Act -- will be upheld. The appeal from Shaun McCutcheon, 46-year-old owner of an Alabama electrical engineering company, is supported in court by the Republican National Committee. They object to a 1970s Watergate-era law restricting someone from giving no more than $48,600 to federal candidates, and $74,600 to political action committees during a two-year election cycle, for a maximum of $123,200. But supporters of existing regulations say the law prevents corruption or the appearance of corruption. Without the limits, they say, one well-heeled donor could in theory contribute a maximum $3.6 million to the national and state parties, and the 450 or so Senate and House candidates expected to run in 2014. Someone who gives that amount, said Justice Elena Kagan, would get "a very, very special place at the table," of grateful candidates and parties. But Justice Samuel Alito dismissed the suggestion as "wild hypotheticals." "How realistic is that," that such willing donors exist, he asked U.S. Solicitor General Donald Verrilli. Alito raised a fairness argument, saying it would be far easier for rich contributors to give to PACs -- political action committees not encumbered by the same limits, than to give directly to candidates under existing restrictions.