It depends what your expectations are, right? If you were expecting, either then or now, that the New Deal was to have "fixed" the economic crisis of the Great Depression, than obviously it failed. If your goal was to prevent such a catastrophe from ever happening again, then it was a stunning success. Others might simply argue the New Deal programs got America through a bad economic time so that recovery was possible, and revolution averted. So it depends on what the criteria or definition of success is.
Whilst statistics such as the unemployment rate and the GDP are important, I do think we need to look wider to see the impact of the New Deal. Let us remember that the situation that was faced by America was incredibly bleak and desperate. The New Deal tried to do something to alleviate the situation and helped many people. Yes, the employment rate and GDP did take a long time to recover, but perhaps that would be expected given the gravity of the situation. Any reflection of the health of a state is only partial, and this needs to be remembered.
It is very hard to argue that the New Deal was an completely successful response to the Great Depression. The unemployment rate in the US did not return to 1929 levels until 1941. The same is true for the Gross Domestic Product. Since these are two major gauges of economic health, it seems clear that the New Deal did not solve the problems of the Depression.
Of course, it is quite possible to argue that things would have been worse had it not been for the New Deal. Unemployment and GDP numbers in 1939 and 1940 were better than they were in 1932. So this argues for the idea that the New Deal was at least somewhat successful.
The New Deal did not end the Great Depression; but it did provide relief and hope to those who suffered from it. The New Deal's program had three elements: Relief, Recovery, Reform. Relief was in the form of the Bank Holiday which allowed people to catch their breaths and ended the runs on banks. Later organizations, such as the Civilian Conservation Corps and the Public Works Administration put people back to work; and Social Security and the Glass Steagal Act which created the Federal Deposit Insurance Corporation provided some insurance against it happening again. Still, private employment did not return as quickly as might have been hoped, and a number of New Deal programs were declared unconstitutional by the Supreme Court. It was the outbreak of World War II, not the New Deal, which ended the Depression. Still, it gave people hope and restored their confidence.