In a speech Thursday to the Economic Club of Washington, D.C., Ryan says, "Tax reform is working. It is improving people's lives."
Voters though, aren't so sure. Polls are showing mixed support for the corporate and household tax cuts President Donald Trump signed into law last year.
The plan is projected to add $1.5 trillion to the deficit, but Republicans say those costs will be covered by economic growth.
Ryan is retiring rather than seeking re-election, but Republicans are counting on the tax plan as part of the election-year message to keep GOP control of the House in fall.
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