It depends on what you mean by "corporations", "government" and "power".
I live in the United States. The US government budget is 3.8 trillion, or about 21% of the GDP. Is any one individual corporation stronger than that in raw economic terms? Heck no. Could any corporation wage war on the United States? Heck no.
But do all multinational corporations have more money than that? Yes. Do all multinational corporations combined have more military resources? No, but they possibly could do so and might if the US were not to represent their needs.
Can an individual corporation affect local, state and even federal government on individual issues? Yes. The U.S. government is not a unified thing: bureaucracies have different and sometimes opposed tasks, and the reality that one can in various ways control the
When Clinton tried a very small stimulus package, it inspired an outroar from investors who threatened to negate the stimulus by simply selling bonds. Clinton later said, "You mean to tell me that the success of the economic program and my re-election hinges on the Federal Reserve and a bunch of f***ing bond traders?" The fact is that capital flight and the power of bondholders does have a massive influence over the US government.
Then again, those with bonds themselves don't want their investment to tank. You can only threaten so much against the world's biggest economy.
It does seem to be the case that America is an oligarchy. Going back to Ferguson's "Golden Rule", that those with the gold make the rules, the US has for decades been heavily influenced by various coalitions of investors in both parties, but in recent years even those institutions that had some power to stop them like the unions have declined in their capabilities.
So corporations run the government, but the government has powers that they can't easily emulate. And corporations aren't a unified bloc either: they oppose each other. That's the entire point of Ferguson's investor theory of politics: the sharp differences in the present party system can be attributed either to populist distractions (abortion, gay marriage, etc.) or to honest disagreements among the leading economic-political class due to their varying needs and perspectives.
The interesting fact about this question isn't the answer, but the fact that it's even close. It means we have allowed multinational corporations to become so massive that their powers rival governments, and indeed eclipse the power of many governments in the developing world. Phillip Morris can bully around countries like Togo and Uruguay because they have money that rivals or exceeds the budgets of those governments and sometimes even the GDP of those governments. Some estimate that 50% of international "trade" is just inter-corporate transfers. Corporations provide the vast majority of jobs, and even if you just look at corporations that are above the level of small-and-medium-sized businesses, the bulk of the workforce is still dependent in some way on corporations. (After all, many smaller businesses only exist in a business-to-business, or B2B, climate, and are dependent on their larger or equally-sized business customers). Corporations have simply immense power.
When you take into account the way that trade agreements have effectively allowed a shadow government of not-insignificant power to overturn national sovereignty in ways that are nearly-exclusively to the benefits of corporations, there is a very strong argument to be made that, yes, corporations are stronger.
I ultimately answered "No" because if the United States were to sharply begin to take control, like they did with Bretton Woods, corporations would have very few options. If we had the death penalty on our books for capital flight like they did in South Korea, I suspect people would toe the line. But the actual power of government, without substantial political support and an informed and active populace, to hedge against corporations is very low.