Jacob Sullum at Reason has a good, brief column worth reading on the similarities between “mavericks” John McCain and Teddy Roosevelt. In short, he recounts how both politicians got caught up in corruption messes, and then used big-government campaign-finance proposals to prove their purity.
I'll also point out that Roosevelt's anti-trust policies have often been used to the advantage of big business, against small business. For instance, credit card companies have blocked small retailers from banding together to negotiate lower interchange rates, and broadcasters used antitrust rules to try to block a merger of smaller satellite companies.
McCain's campaign finance regulations, meanwhile, have also crushed competition in politics, preserving a duopoly, as I wrote when a third party bid in 2008 fizzled out.