some top republicans say that falls short. >> there is not enough. there is not nearly enough, and it simply will not take care of the issues and challenges we have. for example, half the f-18s are now grounded for lack of parts, and we have increased operations both in syria and afghanistan. >> reporter: and new push back from house conservatives. now threatening to derail gop plans to repeal and replace obamacare. you'll vote against this plan if it were to come up? >> i have big concerns, i think a lot of members do with the plan as it is proposed right now. >> reporter: a growing number of house republicans are questioning a central element of the health plan. new refundable tax credits americans would use to buy health insurance. some conservatives view that plan as another entitlement. do you have any concerns with that specifically the concern about this creating potentially new entitlement? >> correct. i think that's the $94 question. do you go from -- again -- a