But Cole says Ryan continues to be the single most convincing member on the issue.
"He has an intellectual credibility that no other member matches. He brings enormous prestige to this," Cole says. "No one else serving on the floor has been the candidate for vice president of the United States, and throughout the entire Republican coalition, he really has been the architect of our thinking on everything from entitlement reform to financial policy to trade."
(RELATED: The Trade Paradox)
Ryan earned his wonkish wunderkind persona early after arriving on Capitol Hill at the age of 28. With his budgets, he helped define his party's vision. And, after serving as the party's vice presidential candidate in 2012, he returned to the House of Representatives with an even higher-profile status. But Ryan has been tested before. When he forged ahead with a bipartisan budget compromise alongside Democratic Sen. Patty Murray, he got flack from outside groups and conservative pundits who viewed the deal as Republican capitulation. Sen. Marco Rubio called it "irresponsible."
But instead of lashing out and saying conservative groups had "lost all credibility," as House Speaker John Boehner did, Ryan called the outside groups "important elements of our conservative family."
And, in his quest to secure votes for TPA, Ryan has relied on the contacts he has forged with outside groups like Heritage and Club for Growth. They wield considerable power over conservative members and could be key to Ryan passing TPA. Ryan has been working to ensure that neither group scores fast-track negatively.
Club for Growth President David McIntosh says that while his group supports TPA, it has concerns about a currency-manipulation measure that is tied to it. The Club would also like to see Boehner promise to let the Export-Import Bank expire as part of the trade negotiation. Yet McIntosh said his group—which supports the underlying free-trade principles—is still leaning toward remaining neutral on the bill if those demands are not met. That decision, he says, has a lot to do with Paul Ryan.
"People trust him and know that when he says something, he is not telling someone else something else. He has a lot of integrity," McIntosh says. "He has the relationship with us that we will certainly listen to him and respect his assessment."
Americans for Tax Reform founder and president Grover Norquist, who supports TPA, said he's been impressed to see Ryan's intensive reach-out operation.
"Ryan spends more face time with more members than any other Republican," Norquist says.
Norquist is doing his own outreach as well on Capitol Hill, and ATR is making calls in 40 districts to encourage voters to contact their members of Congress.