Other opponents have challenged it on environmental and financial grounds.
The finalist, almost always a strong opponent will challenge you for the Cup.
Opponents challenge it as an instrument of American economic colonialism.
Opponents are all but challenging him to shoot the jumpers.
The government insists on many things that its political opponents challenge vociferously.
But opponents challenge the report, the process that produced it and the idea of building the turbine array in the first place.
Opponents have challenged the theory as too far-fetched to be credible.
Opponents have challenged the need for it, contending that lobbying has not been shown to be worse than in the past.
Many people then discovered that their opponents had challenged their right to be on the ballot.
The opponents have challenged the tax in court and mounted a barrage of negative publicity.