If that were to happen, it could prove to be a nearly insurmountable obstacle to the Democrats.

Yet each faces what could be insurmountable obstacles to success.

That is possible because urban school districts face insurmountable obstacles.

A 17-point deficit in a football game does not seem like an insurmountable obstacle.

Although getting advertisers on board will take some effort, it's not an insurmountable obstacle.

Until now, this dispute has been an insurmountable obstacle to agreement.

Based on past experience, I decided that the fat guy at the gate was not an insurmountable obstacle to people who wanted to kill me.

However, can these objectives be achieved, or will they again become yet another insurmountable obstacle?

Several times had he even made the attempt, but was stopped by some insurmountable obstacle.

He had never before come up against such an insurmountable obstacle.