The House Budget Committee chairman was pressed four times on "Fox News Sunday" to refute the Obama campaign's argument GOP presidential nominee Mitt Romney's plan to cut tax rates 20 percent for all Americans would cost $5 trillion.
After the fourth time, he said: "I don't have the -- it would take me too long to go through all of that, but let me say it this way. You can lower tax rates by 20 percent across the board by closing loopholes and still have preferences for the middle class for things like charitable deductions, for home purchases, for healthcare."
Asked about recent polls showing Obama leading Romney, Ryan said, "We're going to win this race."
When moderator Chris Wallace said, "But you're not, at this point -- you're losing," Ryan said: "Look, we can debate polls. I can tell you this: The president is offering four more years of the same. And the president has been very good at distorting the issue, at disguising the truth. He has been very good at distracting the people.
"He can't run on hope and change any more. So he is running on division, on distraction, on distortion to try and win an election by default. Mitt Romney and I are going to give the people a very clear choice," he said.
The latest United Press International-CVoter poll indicated 48 percent of likely voters said they would vote for Obama and 46 percent said they would vote for Romney.
The poll of 773 likely voters Sept. 19-25, released Thursday, had a margin of error of 4.5 percentage points.
The average of all major polls gives Obama a 4.1-point advantage, with the spread ranging from 2 percentage points to 7 points. Many of the polls are within the margin of error.