Journalist and author David Brock said he was concerned about Jeb Bush's decline in popularity during a conversation with HuffPost Live on Wednesday.
"My view is that Jeb Bush is the only viable candidate the Republicans have, but the big story of the last few weeks that's gotten much less coverage than the Trump surge or the falling polls for Hillary is Jeb Bush cratering," Brock said, citing Bush's polling as being a disappointing "3 percent in Iowa, 7 percent in New Hampshire" and "10 percent nationally."
Brock, who founded the progressive non-profit Media Matters for America, worries that Bush's low energy at debates will hurt both his chances at the presidency as well as the Republican party as a whole.
"If he doesn't stand up, stand out and have a strong performance, I don't know what the Republican establishment does because I don't think Donald Trump is a viable candidate for them, and the longer nobody stands up effectively, the entire field gets discredited," he said.
Brock's book, Killing The Messenger, is in stores now.
Watch more from Media Matters founder David Brock's HuffPost Live conversation here.
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