Former New Jersey governor and ABC News Contributor Chris Christie joined ABC News’ Political Director Rick Klein and Congressional Correspondent Mary Bruce on the Powerhouse Politics Podcast to discuss President Donald Trump and GOP messaging in the run-up to the midterms.

Christie expressed concern that Republicans have been “ineffective” in pressing their case with voters on health care – by some measures, the No. 1 issue for voters.

“In some of these competitive House seats in suburban areas, the pre-existing condition issue is one that’s really cutting. And the Republicans to this point, I think, have been pretty ineffective in terms of making their case on why they weren’t going after the pre-existing condition coverage and that we’re going to maintain it,” Christie told Klein and Bruce. “I think you’re being drowned out by the amount of money that Democrats are spending on the issue.”

Republicans defensively raising the issue – largely arguing that they will protect pre-existing conditions -- previous votes to repeal Obamacare notwithstanding – might not work at this point in the campaign, he said.

“It may be too little, too late ... I do think that this was the risk they [Republicans] took,” Christie said. “I always thought it was a bad decision to take on Obamacare first, out of the box, and it’s allowed that issue to be here and be resonating for Democrats.”

“For a year and a half-- and that’s a long time for something to percolate-- and for you to try to come in kind of at the 11th hour with more information from the Republican side, I think it’s hard to pull that off,” Christie said.

Christie acknowledged that the election results will be read as a referendum on Trump.

“He’s the head of the party and he gets credit when the party does well, and he gets some blame when the party does poorly now,” Christie said. “But I don’t think the president, despite what he’s saying, really believes that he can avoid any blame for what happens if it doesn’t go well. He’ll take some blame if it goes better than expected. You can be assured that he’ll be out there taking credit.”

He added that the probability that voters will send a mixed message next week will complicate efforts to develop big takeaways.

“I think it’s very difficult to tell. I do speak of the overwhelming historical theme, which will remain true, the midterm elections are always difficult for the party in power, always difficult for the person in the party who owns the White House,” Christie said.

Every Wednesday, ABC Radio and iTunes bring you the Powerhouse Politics Podcast, which includes headliner interviews and in-depth looks at the people and events shaping U.S. politics. Hosted by ABC News’ Chief White House Correspondent Jonathan Karl and ABC News Political Director Rick Klein.