The U.S. economy appears to have gotten quick out of the gate in the second quarter and it could be on track for 4% growth or higher, analysts say. After strong gains in personal income and consumer spending in April, a bevy of Wall Street firms upped their GDP forecasts. Amherst Pierpont Securities raised its estimate to 4.5% from 4.2%. Macroeconomic Advisers increased its forecast to 4% from 3.6%. Natwest raised its projection to about 4% from 3.2%. Barclays also upped its estimate, but it was near the low end of forecasts. It raised its target to 3.3% from 3%. GDP has only topped 4% three times since the end of the Great Recession in mid-2009.