Washington (CNN) -- When Paul Ryan struggled to explain a budget-balancing timeline under Mitt Romney, he highlighted the difficulty of trying to run a substantive campaign without being too specific. While Ryan's interview Tuesday with Fox News' Brit Hume was no Sarah Palin-Katie Couric moment, the Republican vice presidential candidate's discomfort in answering when Romney's proposal would balance the budget was evident. Ryan, a seven-term congressman from Wisconsin and chairman of the House Budget Committee, said he was unsure when Romney's proposals would balance the federal budget. Romney's plans say he would "put the federal government on a course toward a balanced budget" but does not say when.
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Paul Ryan, a top GOP numbers guy, struggles to explain Mitt Romney's fuzzy budget details
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Part of Ryan's difficulty stems from difference between his and Romney's budget proposals
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Expert: Romney campaign needs to give Ryan some leeway where he can go into specifics
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Otherwise, the professor says, "the Obama campaign will define them"
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@placeholder repeatedly pressed Ryan on the question of "when" Romney's budget would balance.
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The plan we offer in the @placeholder balances the budget.
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And even @placeholder has acknowledged that he and his running mate aren't fully simpatico when it comes to budget matters.
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"I'm sure there are places that my budget is different than his, but we're on the same page as I said before," @placeholder said on the trail Monday.