Wyden made similar remarks in a Monday Huffington Post op-ed that specifically called out GOP presidential candidate Mitt Romney.
The op-ed comes after the Romney campaign last week issued a statement drawing parallels between his Medicare proposals and the Ryan-Wyden plan.
"Mitt Romney — along with a bipartisan group of leaders — has offered a solution that would introduce competition and choice into Medicare, control costs, and strengthen the program for future generations," the statement read.
Wyden went on to raise questions with the Medicare overhaul in Ryan's budget, which was released Tuesday, but fell short of saying he didn't support it. Like last year's Ryan-Wyden proposal, the Ryan budget counts on competition among private healthcare plans to bring costs down.
The backstop if that doesn't happen is lower in the Ryan budget, however. While Ryan-Wyden would have capped growth in per capita Medicare spending at the rate of gross domestic product growth plus 1 percentage point, the Ryan budget proposes a lower rate of GDP growth + 0.5 percentage points.
"I support GDP + 1 percent," Wyden said Tuesday when asked his thoughts on the Ryan budget.