Even for challengers with deep-pocketed governments to support them, that is quite some barrier to entry.

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Lance, however, would have won the primary even if two of his challengers had thrown their support behind the third.

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Would-be challengers have difficulty reaching even the lowest rungs of the competitive ladder, and have no chance of building the global networks clients want.

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Honda is hamstrung on responding to challengers because the vehicle barely breaks even at current exchange rates.

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Even with Big Media on its side, iPod challengers will still face a tough battle to take significant market share from Apple.

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Williams, as expected, were the most consistent challengers to Ferrari, but only occasionally could they even think about beating them.

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