"I believe she's going to win in an electoral landslide and be the most unpopular president in electoral history, which is quite the paradox," Weaver told David Axelrod on "The Axe Files" podcast, produced by the University of Chicago Institute of Politics and CNN.
Weaver, who often works with more moderate, independent Republican candidates -- recently with John Kasich, but most famously with John McCain -- believes Clinton's weak standing will only encourage Republicans to ignore the difficult work of addressing the party's underlying demographic problems and instead coalesce around opposition to Clinton.
"Unfortunately, instead of seeing this as an opportunity for Republicans to do a little self-introspection, a chance to look beyond ourselves, and to rise to the moment -- which would help us grow nationally," said Weaver, "the instinct will be to throw landmines, not to govern and to cause problems above and beyond being just the normal loyal opposition ideologically."
The Republican party is going through "an existential crisis," Weaver argued, and "the damage done demographically and to our long-term chances" by the 2016 campaign will not be solved until Republicans offer a broader, more inclusive vision.
Weaver signaled that he would continue to help Kasich, who he expects will remain active in the ideological battles within the Republican party, which Weaver predicts "will not be for the faint of heart." He also sees Kasich continuing his alliance with President Barack Obama over passage of the Trans-Pacific Partnership, the multinational trade agreement awaiting Senate approval.
"He's going to work his tail off to help the President pass TPP in the lame duck," if it comes to a vote, Weaver said.
As for Kasich's presidential aspirations, Weaver is more circumspect. While allowing that he himself is ready for another presidential run, Weaver made a point to mention Kasich's standing as one of the party's few popular national figures.
"So, could I see him doing it again? Yes," Weaver said. "Could he? I'm not sure he's there yet."
To hear the whole conversation with Weaver, which also covered his experiences growing up as a Democrat in Texas and how the state's politics has changed over the years, his memories of John McCain's 2000 and 2008 primary campaigns, and the personal toll a career in politics has on individuals and their families, click on http://podcast.cnn.com
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